In this video we discuss hydrogen bonds. We cover how do hydrogen bonds form, the different elements that take part in hydrogen bonds, and why doesn't oil and water mix. What are hydrogen bonds? An attractive force called a hydrogen bond can exist between certain molecules. These bonds are weaker than ionic or covalent bonds, because it takes less energy to break these types of bonds, however, a large number of these bonds going on can exert a strong force. Hydrogen bonds are the result of an unequal charge distribution on a molecule, these molecules are said to be polar. If we look at a water molecule, we can see the oxygen atom shares electrons with 2 different hydrogen atoms. So, in total this molecule has 10 protons, 8 from oxygen and 1 each from the hydrogen atoms, and a total of 10 electrons, 2 shared between the oxygen atom and hydrogen atom number one, 2 shared between the oxygen atom and hydrogen atom number 2, and the other 6 non shared electrons from the oxygen atom. So, this water molecule is electrically neutral, but it has a partial positive side, the hydrogen side, and a partial negative side, the oxygen side of the molecule. The electrons are not shared equally within the molecule, as they have a higher probability of being found closer to the nucleus of the oxygen atom, giving that end a slightly negative charge. So, the hydrogen atoms end of the molecule will have a slightly positive charge. These charged ends weakly attach the positive end of one water molecule to the negative end of an adjacent water molecule. When water is in liquid form there a few hydrogen bonds, solid form, many bonds, and when water is steam or gas, there are no bonds, because the molecules are too far apart to form any bonds. Hydrogen bonds only form between hydrogen atoms that are covalently bonded, or bonds where electrons are being shared and not transferred, to an oxygen, nitrogen or fluorine atom. These bonds make water ideal for the chemistry of life. Hydrogen bonds are also important in the structure of proteins and nucleic acids, which we will cover in later videos. So, now we know that water molecules are polar, or have slightly positive and slightly negative ends, and in fact, many lipids, or fats and oils, are not polar. So their molecules share electrons equally in their bonds. So, these are nonpolar molecules. This means that when water and oil come together they do not form bonds with one another. Even when we try to mix them, the water molecules will eventually separate because their polar molecules are attracted to one another and will form hydrogen bonds, separating the water and the nonpolar oil molecules.
Views: 100983 Whats Up Dude
To see all my Chemistry videos, check out http://socratic.org/chemistry Hydrogen bonding can be so confusing, and in this video we talk about some common mistakes. Hydrogen bonds are intermolecular forces between molecules. They form because one atom has a high electronegativity, so it gets a partial negative charge, and the hydrogen gets a partial positive charge.
Views: 574684 Tyler DeWitt
This chemistry video tutorial provides a basic introduction into hydrogen bonding. Hydrogen bonding occurs in molecules when hydrogen is attached to highly electronegative small atoms such as nitrogen, oxygen, and fluorine. Hydrogen bonds are very strong dipole dipole interactions. Molecules that contain hydrogen bonds such as water are very polar. Hydrogen bonds is one of the strongest types of intermolecular forces. This video contains a few examples and illustrations of hydrogen bonds in water and in HF. New Chemistry Video Playlist: https://www.youtube.com/watch?v=bka20Q9TN6M&t=25s&list=PL0o_zxa4K1BWziAvOKdqsMFSB_MyyLAqS&index=1 Access to Premium Videos: https://www.patreon.com/MathScienceTutor Facebook: https://www.facebook.com/MathScienceTutoring/
Views: 13291 The Organic Chemistry Tutor
There are four types of chemical bonds essential for life to exist: Ionic Bonds, Covalent Bonds, Hydrogen Bonds, and van der Waals interactions. We need all of these different kinds of bonds to play various roles in biochemical interactions. These bonds vary in their strengths. In Chemistry, we think of Ionic Bonds and Covalent bonds as having an overlapping range of strengths. But remember, in biochemistry, everything is happening in the context of water. This means Ionic bonds tend to dissociate in water. Thus, we will think of these bonds in the following order (strongest to weakest): Covalent, Ionic, Hydrogen, and van der Waals. Also note that in Chemistry, the weakest bonds are more commonly referred to as “dispersion forces.” Related Chemistry video: Ionic Bonds vs Covalent Bonds http://bit.ly/2cUG6C8 Our series on Biology is aimed at the first-year college level, including pre-med students. These videos should also be helpful for students in challenging high school biology courses. Perfect for preparing for the AP Biology exam or the Biology SAT. Also appropriate for advanced homeschoolers. You can also follow along if you are just curious, and would like to know more about this fascinating subject. ***** Our current biology textbook recommendation is Campbell Biology from Pearson. 10th edition Amazon Link: http://amzn.to/2mahQTi 11th edition Amazon Link: http://amzn.to/2m7xU6w Amazon Used Textbooks - Save up to 90% http://amzn.to/2pllk4B For lighter reading, we recommend: I Contain Multitudes: The Microbes Within Us and a Grander View of Life by Ed Yong http://amzn.to/2pLOddQ Lab Girl by Hope Jahren http://amzn.to/2oMolPg ***** This video was made possible by the generous donations of our Patrons on Patreon. We dedicate this video to our VIP Patron, Vishal Shah. We’re so thankful for your support! ***** Please Subscribe so you'll hear about our newest videos! http://bit.ly/1ixuu9W If you found this video helpful, please give it a "thumbs up" and share it with your friends! If you'd like to support more great educational videos from Socratica, please consider becoming our Patron on Patreon! https://www.patreon.com/socratica ***** Written and Produced by Kimberly Hatch Harrison About our instructor: Kimberly Hatch Harrison received degrees in Biology and English Literature from Caltech before working in pharmaceuticals research, developing drugs for autoimmune disorders. She then continued her studies in Molecular Biology (focusing on Immunology and Neurobiology) at Princeton University, where she began teaching as a graduate student. Her success in teaching convinced her to leave the glamorous world of biology research and turn to teaching full-time, accepting a position at an exclusive prep school, where she taught biology and chemistry for eight years. She is now the head writer and producer of Socratica Studios. ****** Creative Commons Picture Credits: Salt crystals https://en.wikipedia.org/wiki/File:Halit-Kristalle.jpg Author: W.J. Pilsak Hydrogen Bonding in water https://en.wikipedia.org/wiki/File:3D_model_hydrogen_bonds_in_water.svg Author: Qwerter Products in this video: Preparing for the Biology AP* Exam (School Edition) (Pearson Education Test Prep) - http://amzn.to/2qJVbxm Cracking the AP Biology Exam, 2017 Edition: Proven Techniques to Help You Score a 5 (College Test Preparation) - http://amzn.to/2qB3NsZ Cracking the SAT Biology E/M Subject Test, 15th Edition (College Test Preparation) - http://amzn.to/2qJIfHN
Views: 42860 Socratica
Reactants and products in reversible and irreversible chemical reactions. Watch the next lesson: https://www.khanacademy.org/science/biology/water-acids-and-bases/hydrogen-bonding-in-water/v/hydrogen-bonding-in-water?utm_source=YT&utm_medium=Desc&utm_campaign=biology Missed the previous lesson? https://www.khanacademy.org/science/biology/chemistry--of-life/chemical-bonds-and-reactions/v/intermolecular-forces-and-molecular-bonds?utm_source=YT&utm_medium=Desc&utm_campaign=biology Biology on Khan Academy: Life is beautiful! From atoms to cells, from genes to proteins, from populations to ecosystems, biology is the study of the fascinating and intricate systems that make life possible. Dive in to learn more about the many branches of biology and why they are exciting and important. Covers topics seen in a high school or first-year college biology course. About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We've also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to Khan Academy's Biology channel: https://www.youtube.com/channel/UC82qE46vcTn7lP4tK_RHhdg?sub_confirmation=1 Subscribe to Khan Academy: https://www.youtube.com/subscription_center?add_user=khanacademy
Views: 265055 Khan Academy
Atoms are a lot like us - we call their relationships "bonds," and there are many different types. Each kind of atomic relationship requires a different type of energy, but they all do best when they settle into the lowest stress situation possible. The nature of the bond between atoms is related to the distance between them and, like people, it also depends on how positive or negative they are. Unlike with human relationships, we can analyze exactly what makes chemical relationships work, and that's what this episode is all about. If you are paying attention, you will learn that chemical bonds form in order to minimize the energy difference between two atoms or ions; that those chemical bonds may be covalent if atoms share electrons, and that covalent bonds can share those electrons evenly or unevenly; that bonds can also be ionic if the electrons are transferred instead of shared: and how to calculate the energy transferred in an ionic bond using Coulomb's Law. -- Table of Contents Bonds Minimize Energy 01:38 Covalent Bonds 03:18 Ionic Bonds 05:37 Coulomb's Law 05:51 -- Want to find Crash Course elsewhere on the internet? Facebook - http://www.facebook.com/YouTubeCrashCourse Twitter - http://www.twitter.com/TheCrashCourse Tumblr - http://thecrashcourse.tumblr.com Support CrashCourse on Subbable: http://subbable.com/crashcourse
Views: 1784114 CrashCourse
Hydrogen Bonds are found between simple molecules that contain either H-F, H-O or H-N bonds. Two factors affect the effectiveness of Hydrogen bonds and hence the boiling point of the molecule. The first factor is extensiveness of the Hydrogen bond, or the average number of Hydrogen bonds each molecule can form. If a molecule can form more Hydrogen bonds, then during boiling more Hydrogen bonds need to be broken which results in a higher boiling point. The second factor is the polarity of the H-F, H-O and H-N bond. In H-F bond is the most polar hence the hydrogen bond that results from this is the strongest, while H-N bond is the least polar which results in the weakest hydrogen bond. To learn more about each of these factors and when to consider them, watch this video tutorial now! Topic - Chemical Bonding, Physical Chemistry, JC, H2, A Level Chemistry, Singapore Found this video useful? Please LIKE this video and SHARE it with your friends. SUBSCRIBE to my YouTube Channel for new A Level H2 Chemistry video lessons every week! Any feedback, comments or questions to clarify? Suggestions for new video lessons? Drop them in the COMMENTS Section, I would love to hear from you! Do you know you can learn Chemistry Concepts under a minute? Follow me on Instagram for my weekly one-minute video lessons at https://www.instagram.com/chemistryguru/ I am also conducting JC H2 Chemistry classes at Bishan Central, Singapore. With my years of experience tutoring hundreds of JC students since 2010, I am confident that I can make H2 Chemistry Simpler for you too! For more information please visit https://chemistryguru.com.sg/ -~-~~-~~~-~~-~- Please watch my latest video: "Valence Shell Electron Pair Repulsion (VSEPR) Theory and Shapes of Molecules" https://www.youtube.com/watch?v=q_NeyW5pe-Y -~-~~-~~~-~~-~-
Which hydrogen bond is stronger the O, N, F hydrogen bond? The effect of the electronegativity on the strength of the hydrogen bond. Reasons behind the fact that hydrogen bond of water is stronger than HF although fluorine has higher electronegativity. The effect of crystal shape of water on the density of ice. Download material link: https://brighteningmind.wixsite.com/channel or visit us on facebook: @brightmindschannel
Views: 13 Bright Minds
Introduction to ionic, covalent, polar covalent and metallic bonds. Watch the next lesson: https://www.khanacademy.org/science/chemistry/chemical-bonds/types-chemical-bonds/v/electronegativity-trends?utm_source=YT&utm_medium=Desc&utm_campaign=chemistry Missed the previous lesson? https://www.khanacademy.org/science/chemistry/periodic-table/periodic-table-trends-bonding/v/metallic-nature-trends?utm_source=YT&utm_medium=Desc&utm_campaign=chemistry Chemistry on Khan Academy: Did you know that everything is made out of chemicals? Chemistry is the study of matter: its composition, properties, and reactivity. This material roughly covers a first-year high school or college course, and a good understanding of algebra is helpful. About Khan Academy: Khan Academy is a nonprofit with a mission to provide a free, world-class education for anyone, anywhere. We believe learners of all ages should have unlimited access to free educational content they can master at their own pace. We use intelligent software, deep data analytics and intuitive user interfaces to help students and teachers around the world. Our resources cover preschool through early college education, including math, biology, chemistry, physics, economics, finance, history, grammar and more. We offer free personalized SAT test prep in partnership with the test developer, the College Board. Khan Academy has been translated into dozens of languages, and 100 million people use our platform worldwide every year. For more information, visit www.khanacademy.org, join us on Facebook or follow us on Twitter at @khanacademy. And remember, you can learn anything. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to Khan Academy’s Chemistry channel: https://www.youtube.com/channel/UCyEot66LrwWFEMONvrIBh3A?sub_confirmation=1 Subscribe to Khan Academy: https://www.youtube.com/subscription_center?add_user=khanacademy
Views: 2337220 Khan Academy
We compare the effect of the quantum mechanics of the nuclei on hydrogen bonds with strengths ranging from weak, to intermediate, to strong. For details of the calculations behind the video, see our article "Quantum nature of the hydrogen bond," Xin-Zheng Li, Brent Walker and Angelos Michaelides, PNAS, vol. 108, no. 16, pp. 6369-6373, (2011).
Views: 2875 icelcn
This chemistry video tutorial focuses on intermolecular forces such hydrogen bonding, ion-ion interactions, dipole dipole, ion dipole, london dispersion forces and van deer waal forces. It contains plenty of examples and practice problems to help you understand the most important concepts related to this material. General Chemistry Video Playlist: https://www.youtube.com/watch?v=bka20Q9TN6M&list=PL0o_zxa4K1BV-uX6wXQgyqZXvRd0tUUV0&index=3 Access to Premium Videos: https://www.patreon.com/MathScienceTutor Facebook: https://www.facebook.com/MathScienceTutoring/ Here is a list of topics: 1. Ion - Ion dipole interactions of KF and CaO 2. Electrostatic Force and Lattice Energy- The effect of charge and ionic radii or size 3. How To Determine Which Ionic Compound has a Higher Melting Point - NaF vs KCl 4. Ion-Dipole Interactions - NaCl and H2O 5. Definition of a Dipole - Polar Molecules & Charge Separation 6. Dipole-Dipole Interactions of Polar Molecules - Partial Charge Electrostatic Attractions of CO 7. Hydrogen Bonding between Hydrogen, Nitrogen, Oxygen, and Fluorine 8. Intermolecular Forces vs Intramolecular Forces 9. Hydrogen Bonding vs Polar & Nonpolar Covalent Bonds 10. London Dispersion Forces & Van Der Waals Forces 11. Permanent Dipoles and Temporary Induced Dipoles - Distribution of electrons in electron cloud 12. Difference Between Atoms and Ions - Cations vs Anions - Number of Electrons and Protons 13. The relationship between Polarizability and Dispersion Forces 14. How To Determine the Strongest Intermolecular Forces In Compounds Such as MgO, KCl, H2O, CH4, CO2, SO2, HF, CH3OH, LiCl, CH2O, CO, and I2 15. The relationship between Boiling Point and Vapor Pressure 16. Straight Chained vs Branched Alkanes - Boiling Point and Intermolecular Forces - Surface Area 17. Ranking Boiling Point In Order of Increasing Strength for I2, Br2, F2, and Cl2 18. Polar and Nonpolar Organic Compounds - Polarity and Water Solubility 19. Ranking Boiling In Decreasing Order For HF, HCl, HBr, and HI 20. The effect of Molar Mass and Number of electrons on the Overall Intermolecular Force / LDF
Views: 398974 The Organic Chemistry Tutor
H2O molecules have two Hydrogens bonded to an extremely electronegative Oxygen. The H therefore has strong partial positive charge. The Oxygen on the other hamd has two spare lone pairs which have high charge density. So overall two lone pairs will attract two partial positive H. In NH3, Nitrogen has only one lone pair but three partial positive Hydrogen that are directly bonded to electronegative Nitrogen. Now 1 lone pair on N will only attract 1 partial positive H. 2 partial positive will then not be able to attract lone pairs as lone pairs are not available. so fewer hydrogen bonds will be formed. In HF, there is only 1 partial positive H but three lone pairs on Flourine. So again, two extra lone pairs will not be able to form Hydrogen bonds due to non availability of partial positive H, so few Hydrogen bonds will be formed in HF. Hence NH3 and HF will have lesser melting and boiling points compared to H2O. For more Video Lectures for O Levels, A Levels, IB Diploma, AP Courses & Edexcel: https://www.megalecture.com https://www.youtube.com/megalecture For Skype/Whiteboard Subject Experts and Tutors and Free Online Trial Classes, Contact: [email protected]
Views: 476 Mega Lecture
How hydrogen "bonding" can occur is discussed, as well as the important consequences of this fairly strong intermolecular force. Table of Contents: 00:00 - C. Hydrogen Bonding 01:11 - Boiling pts. With hydrogen bonds 01:16 - 01:39 - Boiling pts. With hydrogen bonds 03:33 - 03:42 - C. Hydrogen Bonding 04:09 - 04:49 - 06:28 - 06:55 - Hydrogen bonding is responsible for: 07:30 - Hydrogen bonding is responsible for: 09:00 - Hydrogen bonding is responsible for: 09:25 - 09:43 - Hydrogen Bonds in Ice 09:46 - 10:14 - 12:39 - 13:11 - II. Liquids and Solids (13.3)
Views: 417 Wendy Doherty
My friend and I wrote a rap for our AP Chemistry class. the beat is ratatat beat 1. Lyrics: (J-Gadsby) Dropping H-bombs about these h-bonds you know the bonds are strong they get all the blondes and it aint magic no harry potter no wands happy days when it bonds fo to the o to the n the fons (A-rizzle) dipole dipole you know how we roll gangster love from the streets they have their moment bonding strong but not so potent out of all the forces theyre the most hood getting into fights but maybe just misunderstood the ray lewis of molecules, they lay the wood (chorus) this is the chorus we wrote this song with a thesaurus all about intermolecular forces cause chemistry is one of our favorite courses this lines here to take up time cause we couldnt think of a better rhyme all about intermolec forces cause chemistry's one of our favorite courses (J-Gadsby) how come every time that you come around my london dispersion force just won't go down study them all week find out that theyre weak can barely hold a molecule that aint tongue in cheek get stronger with more mass like students stuck in class the weakest in the stack thats wickity wickity wack alone in their own wolf pack now i throw it to a-rizzle he's on the attack (A-rizzle) yo, so now you know, mr solo do lo intermolecular forces like a boss, fo sho h bonds like james bond shaken not stirred the strongest of the strong medium is the dipole dipole i love chem, but i'm on parole last we got the LDF, too weak to say we da best (Chorus) (A-rizzle) yo, rapping off the walls about van der waals (J-gadsby) Its hard to keep a straight face a-rizzles bringing the sizzle hes just gonna put this beat in its place chemistry 2010-2011 the course is rapped
Views: 274 John Gaddis
052 - Bond Length and Bond Energy In this video Paul Andersen explains how the bond length and bond energy are calculated using an energy distance graph. The strength of the bond is determined by the charges in the constituent atoms. As the charge increases the bond energy increases and the bond length decreases. Increasing numbers of bonds will also increase the energy and decrease the length. Do you speak another language? Help me translate my videos: http://www.bozemanscience.com/translations/ Music Attribution Title: String Theory Artist: Herman Jolly http://sunsetvalley.bandcamp.com/track/string-theory All of the images are licensed under creative commons and public domain licensing: Cdang. Deutsch: Prinzip Des Laue-Verfahrens: Ein Einfallender Monochromatischer Röntgenstrahl Trifft Auf Ein Einkristall, Wird an Diesem in Bestimmte Richtungen Gebeugt Und Erzeugt Auf Der Dahinter Liegenden Fotoplatte Ein Beugungsmuster, March 30, 2009. Own work. http://commons.wikimedia.org/wiki/File:Cliche_de_laue_principe.svg. "File:Ethane-A-3D-balls.png." Wikipedia, the Free Encyclopedia. Accessed December 15, 2013. http://en.wikipedia.org/wiki/File:Ethane-A-3D-balls.png. "File:Hexamethylbenzene-3D-balls.png." Wikipedia, the Free Encyclopedia. Accessed December 15, 2013. http://en.wikipedia.org/wiki/File:Hexamethylbenzene-3D-balls.png.
Views: 157298 Bozeman Science
Ionic Bond, Covalent Bond, James Bond, so many bonds! What dictates which kind of bond will form? Electronegativity values, of course. Let's go through each type and what they're all about. To support this channel and keep up on STEM news at the same time, click on the link below and subscribe to this FREE newsletter: http://www.jdoqocy.com/click-9021241-13591026 Subscribe: http://bit.ly/ProfDaveSubscribe [email protected] http://patreon.com/ProfessorDaveExplains http://professordaveexplains.com http://facebook.com/ProfessorDaveExpl... http://twitter.com/DaveExplains General Chemistry Tutorials: http://bit.ly/ProfDaveGenChem Organic Chemistry Tutorials: http://bit.ly/ProfDaveOrgChem Biochemistry Tutorials: http://bit.ly/ProfDaveBiochem Classical Physics Tutorials: http://bit.ly/ProfDavePhysics1 Modern Physics Tutorials: http://bit.ly/ProfDavePhysics2 Mathematics Tutorials: http://bit.ly/ProfDaveMaths Biology Tutorials: http://bit.ly/ProfDaveBio American History Tutorials: http://bit.ly/ProfDaveAmericanHistory
Views: 285060 Professor Dave Explains
This organic chemistry video tutorial provides a basic introduction into intermolecular forces, hydrogen bonding, and dipole dipole interactions. It explains how to determine which molecule has a higher boiling point and which has a higher solubility in water. Subscribe: https://www.youtube.com/channel/UCEWpbFLzoYGPfuWUMFPSaoA?sub_confirmation=1 Access to Premium Videos: https://www.patreon.com/MathScienceTutor https://www.facebook.com/MathScienceTutoring/ New Organic Chemistry Playlist https://www.youtube.com/watch?v=6unef5Hz6SU&index=1&list=PL0o_zxa4K1BXP7TUO7656wg0uF1xYnwgm&t=0s
Views: 42754 The Organic Chemistry Tutor
This clip provides an overview of chemical bonds, explaining that a chemical bond is not a physical structure but an energy relationship that involves interactions between the electrons of the reacting atoms. The clip also discusses the various types of chemical bonds (ionic, covalent and hydrogen).
Views: 2426 INTELECOM
Petr Tolstoy: Cooperativity of Strong Hydrogen Bonds Studied by Liquid State NMR Spectroscopy In English
Views: 43 SPINUS
Stronger intermolecular forces = LOWER vapor pressure Weaker intermolecular forces = HIGHER vapor pressure Check me out: http://www.chemistnate.com
Views: 96467 chemistNATE
Strong versus Weak bonds | Part 3 of Atomic & Molecular Bonds & Interactions | Get better grade in exam. | Easy learning in just 2 minutes. Illustrated animations. These videos use visual learning technique, which are compilation of knowledge that already exists all over the internet; I compiled all those theories, concepts, definitions, laws, equations, interpretations, etc., so the viewers can save their time watching these. So,……… relax, sit down and watch my videos, learn by heart and go to the exams with your heads high. No worries. chemical bonds, molecular interactions, strong bonds, weak bonds, covalent, non-covalent, ionic, hydrogen-bonding, van der Waals, London Dispersion, polar, non-polar, metallic, atomic orbital, molecular orbital, electron sharing, binding, anti-binding, primary bonds, secondary bonds, electronegativity, dipole moment, Find me on TeacherTube: https://www.teachertube.com/user/channel/anjanasen Many thanks to websites: http://www.audioremover.com/ https://freesound.org/ https://handbrake.fr/
Views: 185 Anjana Sen
Watch more videos on http://www.brightstorm.com/science/chemistry SUBSCRIBE FOR All OUR VIDEOS! https://www.youtube.com/subscription_center?add_user=brightstorm2 VISIT BRIGHTSTORM.com FOR TONS OF VIDEO TUTORIALS AND OTHER FEATURES! http://www.brightstorm.com/ LET'S CONNECT! Facebook ► https://www.facebook.com/brightstorm Pinterest ► https://www.pinterest.com/brightstorm/ Google+ ► https://plus.google.com/+brightstorm/ Twitter ► https://twitter.com/brightstorm_ Brightstorm website ► https://www.brightstorm.com/
Views: 442726 Brightstorm
Why do different liquids boil at different temperatures? It has to do with how strongly the molecules interact with each other. Find out all the different ways, and how to use them to make predictions about matter! To support this channel and keep up on STEM news at the same time, click on the link below and subscribe to this FREE newsletter: http://www.jdoqocy.com/click-9021241-13591026 Subscribe: http://bit.ly/ProfDaveSubscribe [email protected] http://patreon.com/ProfessorDaveExplains http://professordaveexplains.com http://facebook.com/ProfessorDaveExpl... http://twitter.com/DaveExplains General Chemistry Tutorials: http://bit.ly/ProfDaveGenChem Organic Chemistry Tutorials: http://bit.ly/ProfDaveOrgChem Biochemistry Tutorials: http://bit.ly/ProfDaveBiochem Classical Physics Tutorials: http://bit.ly/ProfDavePhysics1 Modern Physics Tutorials: http://bit.ly/ProfDavePhysics2 Mathematics Tutorials: http://bit.ly/ProfDaveMaths Biology Tutorials: http://bit.ly/ProfDaveBio American History Tutorials: http://bit.ly/ProfDaveAmericanHistory
Views: 637289 Professor Dave Explains
This song explains the hydrogen bond attractive force and why water molecules have strong attractions despite their small relative size. Music and lyrics copyright 2007 by Mark Rosengarten. All rights reserved. Lyrics: Hydrogen bonds Bugs in a pond Walking across Some looking lost Why dont they fall in? Surface tension Hydrogen bonds Hydrogen bonds Small molecules They arent fools They can attract They wont attack H positive O negative Opposite ends They become friends H2O small Whys it liquid at all (CO2 gas Its got more mass) H2Os got Hydrogen bonds Bugs, they can cross Walking the pond Capillary Action, you see Cause it must be A high E.N.D. (ELECTRONEGATIVITY DIFFERENCE!!!) Got polar ends (The molecule bends) The O at the joint High boiling point Its not volatile (Just not its style) Hydrogen bonds Hydrogen bonds H on one side N, O or F on the other Its really polar And attracts like a mother! Dipole attraction from hell I love hydrogen bondssowell!!!!!
Views: 38880 Mark Rosengarten
Van der Waals forces: London dispersion forces, dipole-dipole forces, and hydrogen bonding. Watch the next lesson: https://www.khanacademy.org/science/chemistry/states-of-matter-and-intermolecular-forces/introduction-to-intermolecular-forces/v/solubility?utm_source=YT&utm_medium=Desc&utm_campaign=chemistry Missed the previous lesson? https://www.khanacademy.org/science/chemistry/states-of-matter-and-intermolecular-forces/states-of-matter/v/phase-diagrams?utm_source=YT&utm_medium=Desc&utm_campaign=chemistry Chemistry on Khan Academy: Did you know that everything is made out of chemicals? Chemistry is the study of matter: its composition, properties, and reactivity. This material roughly covers a first-year high school or college course, and a good understanding of algebra is helpful. About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We've also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content. For free. For everyone. Forever. #YouCanLearnAnything Subscribe to Khan Academy’s Chemistry channel: https://www.youtube.com/channel/UCyEot66LrwWFEMONvrIBh3A?sub_confirmation=1 Subscribe to Khan Academy: https://www.youtube.com/subscription_center?add_user=khanacademy
Views: 772350 Khan Academy
Hank teaches us why water is one of the most fascinating and important substances in the universe. Follow SciShow on Twitter: http://www.twitter.com/scishow Like SciShow on Facebook: http://www.facebook.com/scishow Review: Re-watch = 00:00 Introduction = 00:42 Molecular structure & hydrogen bonds = 01:38 Cohesion & surface tension = 02:46 Adhesion = 03:31 Hydrophilic substances = 04:42 Hydrophobic substances = 05:14 Henry Cavendish = 05:49 Ice Density = 07:45 Heat Capacity = 09:10 Crash Course Biology is now available on DVD! http://dftba.com/product/1av/CrashCourse-Biology-The-Complete-Series-DVD-Set Citations: http://www.extension.umn.edu/distribution/youthdevelopment/components/0328-02.html http://www.uni.edu/~iowawet/H2OProperties.html http://www.hometrainingtools.com/properties-water-science-teaching-tip/a/1274/ http://science.howstuffworks.com/environmental/earth/geophysics/h2o7.htm http://www.robinsonlibrary.com/science/chemistry/biography/cavendish.htm http://chemistry.mtu.edu/~pcharles/SCIHISTORY/HenryCavendish.html http://www.nndb.com/people/030/000083778/ http://www.notablebiographies.com/Ca-Ch/Cavendish-Henry.html TAGS: water, hydrogen, oxygen, molecule, covalent bond, cohesion, adhesion, polarity, hydrogen bond, surface tension, capillary action, hydrophilic, hydrophobic, ionic bond, ion, universal solvent, henry cavendish, chemistry, specific gravity, density, heat capacity, evaporation, biology, crashcourse, crash course, hank green Support CrashCourse on Subbable: http://subbable.com/crashcourse
Views: 3172745 CrashCourse
This chemistry tutorial video explains how oxygen, nitrogen & carbon make covalent chemical bonds to school & science students . The video shows how the protons and electron shells, and especially the number of electrons in the outer shells determine how many bonds oxygen, nitrogen and carbon can make. Four important molecules, water H2O, ammonia NH3, and methane CH4 are discussed. Subscribe to watch more online chemistry courses & science videos: http://www.youtube.com/channel/UCiX8pAYWBppIbtUZTfGnRJw?sub_confirmation=1 About Atomic School: Atomic School supports the teaching of Atomic Theory to primary school & science students . We provide lesson plans, hands-on classroom resources, demonstration equipment, quizzes and a Teacher's Manual to primary school teachers. Animated videos that clearly explain the scientific ideas supports learning by both teachers and students. As a teacher, you don't have to look anywhere else to implement this program. Our work has been verified by science education researchers at the University of Southern Queensland, Dr Jenny Donovan and Dr Carole Haeusler, who confirm that primary students are capable of learning much more complex scientific concepts than previously thought, and crucially, that they love it. Students run to class! The program has been trialed in Australian schools as well as schools in the Philippines, Iran and India. It is conducted as holiday workshops at the Australian Nuclear Science and Technology Organisation, the Queensland Museum as well as the World Science Festival. It has attracted wide media interest, including TV, radio and print, and the research data has been presented at prestigious American Education Research Association and Australian Science Education Research Association conferences. Atomic Theory underlies all the other sciences- genetics, electronics, nanotechnology, engineering and astronomy- so an early understanding will set them up for a more successful learning sequence for all their science subjects, and support their mastery of mathematics as well. We also have extension programs that cover Biology, Physics and Astronomy to an equal depth. About Ian Stuart (Email: [email protected]): The founder of Atomic School, Ian Stuart, taught Chemistry and Physics for 25 years at senior levels before he realized that his 8-year old son, Tom, could understand Atomic Theory at a much deeper level than he expected. After visiting Tom's class at school, he discovered that his peers could also grasp the abstract scientific concepts, as well as apply it usefully to the real world. Ian then developed a program to teach the advanced concepts of high school Chemistry, Physics and Biology to students 10 years younger than they normally would. He found that this engaged their interest in modern science early, and sustained it through to high school and beyond. It also sets them up for future success in their academic and career paths. Ian has a Bachelor's Degree in Chemistry from the University of Queensland and a Master's degree in Electrochemistry from the University of Melbourne. Connect with Atomic School on social media: http://facebook.com/AtomicSchool http://twitter.com/AtomicSchools http://instagram.com/AtomicSchools Video transcript:
Views: 148969 AtomicSchool
Chemistry: Ionic Bonds vs Covalent Bonds (which is stronger?) Ionic Bonds and Covalent bonds are both considered STRONG intramolecular forces. But do you know which is stronger? You'd think this was a straightforward question. But there's more to it! Each of these bonds has a range of strengths. In this video, we'll discuss how the strength of Ionic Bonds and Covalent bonds are measured so you can compare two chemical bonds. You can click on the links below to jump to sections in the lesson: 0:25 Definitions of ionic and covalent bonds 1:45 Measuring the strength of ionic bonds (lattice energy) 3:08 Some typical lattice energies of ionic bonds 3:50 Measuring the strength of covalent bonds (bond enthalpy) 4:19 Some typical bond enthalpies of covalent bonds Here are our more in-depth videos about the individual bonds. Ionic Bonds: http://bit.ly/1UWsJRL Covalent Bonds: http://bit.ly/1HYZmow3 Metallic Bonds: http://bit.ly/1UoASiZ Intermolecular Forces: http://bit.ly/2xAnoMt ///////////////////////// Our Periodic Table app is FREE in the Google Play store! http://goo.gl/yg9mAF Don't miss our other chemistry videos: https://www.youtube.com/watch?v=aQw9G... Please Subscribe so you'll hear about our newest videos! http://bit.ly/1ixuu9W If you found this video helpful, please give it a "thumbs up" and share it with your friends! ///////////////////////// To support more videos from Socratica, visit Socratica Patreon https://www.patreon.com/socratica http://bit.ly/29gJAyg Socratica Paypal https://www.paypal.me/socratica We also accept Bitcoin! :) Our address is: 1EttYyGwJmpy9bLY2UcmEqMJuBfaZ1HdG9 ///////////////////////// We recommend the following books: Brown and LeMay Chemistry: The Central Science 13th edition: http://amzn.to/2n5SXtB 14th edition: http://amzn.to/2mHk79f McGraw/Hill Chemistry by Chang & Goldsby http://amzn.to/2mO2khf Uncle Tungsten: Memories of a Chemical Boyhood by Oliver Sacks http://amzn.to/2nlaJp0 Napoleon's Buttons: How 17 Molecules Changed History http://amzn.to/2lJZzO3 ///////////////////////// Written and Produced by Kimberly Hatch Harrison About our instructor: Kimberly Hatch Harrison received degrees in Biology and English Literature from Caltech before working in pharmaceuticals research, developing drugs for autoimmune disorders. She then continued her studies in Molecular Biology (focusing on Immunology and Neurobiology) at Princeton University, where she began teaching as a graduate student. Her success in teaching convinced her to leave the glamorous world of biology research and turn to teaching full-time. Kimberly taught AP Biology and Chemistry at an exclusive prep school for eight years. She is now the head writer and producer of Socratica Studios. Creative Commons Picture Credits: Butter http://en.wikipedia.org/wiki/File:Western-pack-butter.jpg Author: Steve Karg, aka Skarg sodium chloride 3D lattice http://en.wikipedia.org/wiki/File:NaC... Author: Raj6
Views: 45957 Socratica
There are two different types of hydrogen bonds. They are Intermolecular bonding and Intramolecular bonding. i) Intermolecular hydrogen bonding. This type of bond is formed between the two molecules of the same or different compounds. Some examples of the compounds exhibiting intermolecular hydrogen bonds are : Hydrogen fluoride and water. 1. Hydrogen fluoride, H F. In the solid state, hydrogen fluoride consists of long zig-zag chains of molecules associated by hydrogen bonds as shown in the figure. Therefore, hydrogen fluoride is represented as HFN. 2. Water In water molecule, the electronegative oxygen atom forms two polar covalent bonds with two hydrogen atoms. The oxygen atom due to its higher electronegativity acquires partial negative charge and the two hydrogen atoms acquire partial positive charge. The negatively charged oxygen forms two hydrogen bonds with two positively charged hydrogen atoms of two neighbouring molecules. Each oxygen atom is tetrahedrally surrounded by four hydrogen atoms as shown in visual. Hydrogen bonding in water results in a hydrogen bridge (HOH) network extending in three dimensions and the associated water molecule may be expressed as H Two O N. ii) Intramolecular hydrogen bonding. This type of bond is formed between hydrogen atom and Nitrogen, Oxygen or Flurine atom of the same molecule. This type of hydrogen bonding is commonly called chelation and is more frequently found in organic compounds. Intramolecular hydrogen bonding is possible when a six or five membered rings can be formed. Importance of H-bonding i) Life would have been impossible without liquid water which is the result of intermolecular H-bonding in it. ii) Hydrogen bonding increase the rigidity and strength of wood fibres and thus makes it an article of great utility to meet requirements of housing, furniture, etc. iii) The cotton, silk or synthetic fibres also own their rigidity and tensile strength to hydrogen bonding. iv) Most of our food materials such as carbohydrates and proteins also consist of hydrogen bonding. v) Hydrogen bonding also exists in various tissues, organs, skin, blood and bones.
Views: 3014 Easy Tips 4 Learner
This video introduces hydrogen bonds. Table of Contents: 00:29 - What I want you to be able to do with today’s information: 00:38 - 06:27 - Hydrogen Bonding 07:39 - 08:42 - Hydrogen Bonding 09:15 - 10:10 - An σ-helix is an important secondary structure type in which the peptide chain is held in a spiral arrangement by hydrogen bonds between amino acids that are close together. 10:32 - A β-pleated sheet is an important secondary structure type in which the peptide chain is held fully extended by hydrogen bonds between amino acids that are far apart. 10:59 - Notice that there are multiple secondary structures 11:31 -
Views: 499 Jay Shore
View full lesson: http://ed.ted.com/lessons/why-does-ice-float-in-water-george-zaidan-and-charles-morton Water is a special substance for several reasons, and you may have noticed an important one right in your cold drink: ice. Solid ice floats in liquid water, which isn't true for most substances. But why? George Zaidan and Charles Morton explain the science behind how how hydrogen bonds keep the ice in your glass (and the polar ice caps) afloat. Lesson by George Zaidan and Charles Morton, animation by Powerhouse Animation Studios Inc.
Views: 812784 TED-Ed
Visit http://ilectureonline.com for more math and science lectures! In this video I will explain the hydrogen bond (dipole-diplole): forces 4.
Views: 1387 Michel van Biezen
Twitter: @staceyjaphta Instagram: @staceyjaphta This is a song I wrote a couple of weeks ago, it's called "Hydrogen Bond". I wrote it for the graduating seniors 2013. I've been very scared to upload original songs on youtube, but I've finally got the courage. A hydrogen bond- written by Stacey Japhta Chords: (No capo) G, Cad9, Em7, Cad9 Verse 1 It's gonna take some time for me To settle down It's hard when you're right for me But I can't have you near Chorus Can 1000 miles break a hydrogen bond Built off love this strong Noooo You're the sugar to my phosphate The base of my life You do more then suffice Verse 2 One day has been enough I want you back To see you smile I'd risk all Chorus Can 1000 miles break a hydrogen bond Built off love this strong Noooo You're the sugar to my phosphate The base of my life You do more then suffice Coda I didn't think that I could fall in love Something so simple turned into A whole new world And you opened eyes Expanded my arisen Chorus Can 1000 miles break a hydrogen bond Built off love this strong Noooo You're the sugar to my phosphate The base of my life You do more then suffice
Views: 2581 Stacey Japhta
Chemical Bonding A chemical bond results from strong electrostatic interactions between two atoms. The nature of the atoms determines the kind of bond. COVALENT bonds result from a strong interaction between NEUTRAL atoms Each atom donates an electron resulting in a pair of electrons that are SHARED between the two atoms For example, consider a hydrogen molecule, H2.When the two hydrogen, H, atoms are far apart from each other they do not feel any interaction. As they come closer each “feels” the presence of the other. The electron on each H atom occupies a volume that covers both H atoms and a COVALENT bond is formed. Once the bond has been formed, the two electrons are shared by BOTH H atoms. An electron density plot for the H2 molecule shows that the shared electrons occupy a volume equally distributed over BOTH H atoms. Potential energy (kJ/mol) Separation (Å) It is also possible that, as two atoms come closer, one electron is transferred to the other atom. The atom that gives up an electron acquires a +1 charge and the other atom, which accepts the electron acquires a –1 charge. The two atoms are attracted to each other through Coulombic interactions – opposite charges attract – resulting in an IONIC bond. Animation Potential energy (kJ/mol) Separation (Å) What factors determine if an atom forms a covalent or ionic bond with another atom? The number of electrons in an atom, particularly the number of the electrons furthest away from the nucleus determines the atom’s reactivity and hence its tendency to form covalent or ionic bonds. These outermost electrons are the one’s that are more likely to “feel” the presence of other atoms and hence the one’s involved in bonding i.e. in reactions. Chemistry of an element depends almost entirely on the number of electrons, and hence its atomic number. The periodic table By the late 1800’s it was realized that elements could be grouped by similar chemical properties and that the chemical and physical properties of elements are periodic functions of their atomic numbers – PERIODIC LAW. The arrangements of the elements in order of increasing atomic number, with elements having similar properties placed in a vertical column, is called the PERIODIC TABLE. Columns are called GROUPS (FAMILIES) and rows are called PERIODS. Elements in a group have similar chemical and physical properties. The total number of electrons within a group is different, increasing in number down a group However, the number of electrons furthest away from the nucleus, called the OUTER or VALENCE electrons is the same for all elements in a group. Groups are referred to by names, which often derive from their properties I – Alkali metals; II – Alkaline Earth metals VII – Halogens; VIII – Noble gases The elements in the middle block are called TRANSITION ELEMENTS Elements in the A group are diverse; metals and non-metals, solids and gases at room temperature. The transition elements are all metals, and are solids at room temp, except for Hg. Among the transition elements are two sets of 14 elements - the LANTHANIDES and the ACTINIDES Physical and Chemical properties such as melting points, thermal and electrical conductivity, atomic size, vary systematically across the periodic table. Elements within a column have similar properties Atomic radius (Å) A “zig-zag” division of the table divides metals from non-metals. Elements to the left of the zig-zag line are metals (except for hydrogen, which is unique) and to the right are non-metals. Elements along the border have intermediate properties and are called metalloids.
Views: 153 SliderBase
View full lesson: http://ed.ted.com/lessons/how-polarity-makes-water-behave-strangely-christina-kleinberg Water is both essential and unique. Many of its particular qualities stem from the fact that it consists of two hydrogen atoms and one oxygen, therefore creating an unequal sharing of electrons. From fish in frozen lakes to ice floating on water, Christina Kleinberg describes the effects of polarity. Lesson by Christina Kleinberg, animation by Alan Foreman.
Views: 412854 TED-Ed
To see all my Chemistry videos, check out http://socratic.org/chemistry This video is an introduction to ionic bonding, which is one type of chemical bonding. Ionic bonds hold together metal and nonmetal atoms. In ionic bonding, electrons are transferred from a metal atom to a nonmetal atom, creating ions. These ions have opposite charge, so they stick together. Creative Commons Attribution-NonCommercial CC BY-NC
Views: 1073890 Tyler DeWitt
This video looks at how to determine polarity in a molecule by understanding how the bond polarities, molecule shape, and outside atoms influence polarity using bond polarity vector addition. This includes a flow chart that guides you through the various decisions needed to determine if a molecule is polar or not. Wikipedia 1/1/2018: In chemistry, polarity is a separation of electric charge leading to a molecule or its chemical groups having an electric dipole or multipole moment. Polar molecules must contain polar bonds due to a difference in electronegativity between the bonded atoms. A polar molecule with two or more polar bonds must have a geometry which is asymmetric in at least one direction, so that the bond dipoles do not cancel each other. While the molecules can be described as "polar covalent", "nonpolar covalent", or "ionic", this is often a relative term, with one molecule simply being more polar or more nonpolar than another. However, the following properties are typical of such molecules. A molecule is composed of one or more chemical bonds between molecular orbitals of different atoms. A molecule may be polar either as a result of polar bonds due to differences in electronegativity as described above, or as a result of an asymmetric arrangement of nonpolar covalent bonds and non-bonding pairs of electrons known as a full molecular orbital. Polar molecules The water molecule is made up of oxygen and hydrogen, with respective electronegativities of 3.44 and 2.20. The dipoles from each of the two bonds (red arrows) add together to make the overall molecule polar. A polar molecule has a net dipole as a result of the opposing charges (i.e. having partial positive and partial negative charges) from polar bonds arranged asymmetrically. Water (H2O) is an example of a polar molecule since it has a slight positive charge on one side and a slight negative charge on the other. The dipoles do not cancel out resulting in a net dipole. Due to the polar nature of the water molecule itself, polar molecules are generally able to dissolve in water. Other examples include sugars (like sucrose), which have many polar oxygen–hydrogen (−OH) groups and are overall highly polar. If the bond dipole moments of the molecule do not cancel, the molecule is polar. For example, the water molecule (H2O) contains two polar O−H bonds in a bent (nonlinear) geometry. The bond dipole moments do not cancel, so that the molecule forms a molecular dipole with its negative pole at the oxygen and its positive pole midway between the two hydrogen atoms. In the figure each bond joins the central O atom with a negative charge (red) to an H atom with a positive charge (blue). The hydrogen fluoride, HF, molecule is polar by virtue of polar covalent bonds – in the covalent bond electrons are displaced toward the more electronegative fluorine atom. Ammonia, NH3, molecule the three N−H bonds have only a slight polarity (toward the more electronegative nitrogen atom). The molecule has two lone electrons in an orbital, that points towards the fourth apex of the approximate tetrahedron, (VSEPR). This orbital is not participating in covalent bonding; it is electron-rich, which results in a powerful dipole across the whole ammonia molecule. Resonance Lewis structures of the ozone molecule In ozone (O3) molecules, the two O−O bonds are nonpolar (there is no electronegativity difference between atoms of the same element). However, the distribution of other electrons is uneven – since the central atom has to share electrons with two other atoms, but each of the outer atoms has to share electrons with only one other atom, the central atom is more deprived of electrons than the others (the central atom has a formal charge of +1, while the outer atoms each have a formal charge of −1⁄2). Since the molecule has a bent geometry, the result is a dipole across the whole ozone molecule. When comparing a polar and nonpolar molecule with similar molar masses, the polar molecule in general has a higher boiling point, because the dipole–dipole interaction between polar molecules results in stronger intermolecular attractions. One common form of polar interaction is the hydrogen bond, which is also known as the H-bond. For example, water forms H-bonds and has a molar mass M = 18 and a boiling point of +100 °C, compared to nonpolar methane with M = 16 and a boiling point of –161 °C. Nonpolar molecules A molecule may be nonpolar either when there is an equal sharing of electrons between the two atoms of a diatomic molecule or because of the symmetrical arrangement of polar bonds in a more complex molecule. Not every molecule with polar bonds is a polar molecule. Carbon dioxide (CO2) has two polar C=O bonds, but the geometry of CO2 is linear so that the two bond dipole moments cancel and there is no net molecular dipole moment; the molecule is nonpolar.
Views: 175837 Crash Chemistry Academy
http://www.chemistry.jamesmungall.co.uk Acid Base Chemistry 4. Acids a. Defining strong acids and weak acids b. Strong acids i. What makes a strong acid? ii. How to calculate the pH of a strong acid 4. Strong acids. Why are some compounds acidic [slide 1] In this tutorial we are going to ask the question, "Why are some compounds acidic?", and in answering this we are going to look at Why acids shouldn't exist, we'll define and identify strong acids, calculate pH of strong acids, and then explain why some compounds are acidic in terms of stabilized anions and bond strength. [slide 2] Why acids shouldn't exist. If we have a non-metal ion, here shown as A-, we would expect this to react with H+ to form an A-H molecule, because non-metals bond covalently. So how can it be that we have a substance in which the two non-metals decide to break apart into ions? That is what you would expect to happen for bonding between a metal and a non-metal, not two non-metals. But when A- is one of a few specific atoms or groups of atoms this does actually occur. [slide 3] So the specific groups we are talking about are NO3-, HSO4- and Cl-. All of these are non-metals, yet they do not make a covalent bond with H+ ions in solution. Indeed they remain as ions. And this is a definition of strong acid; it is a compound which in solution breaks apart to form H+ ions and a neutral anion. For nitric acid the neutral anion is NO3-, for sulphuric acid it is HSO4- and for hydrochloric acid it is Cl-. We write them as HNO3, H2SO4 and HCl, but in fact these molecules have broken apart into ions in solution. [slide 4] To calculate the pH of a strong acid, we take the concentration of the acid, so for example 1moldm-3 HNO3, and then the concentration of the H+ ions will be the same as this, i.e. 1moldm-3, because all of the the HNO3 molecules have broken apart to form H+ and NO3- ions. This gives an H+ concentration of 1moldm-3, and pH is then -log 1 which is zero. For 0.01moldm-3 HCl, the H+ concentration is 0.01 moldm-3, and so the pH is -log 0.01 which is 2. Therefore, to work out the pH of a strong acid, the only data you need is the concentration of the acid. [slide 5] To explain the behaviour of these specific compounds we need to consider the stability of the anion formed. For a strong acid, they must have a stabilized anion. In other words, the negative charge must be tightly held by the anion, and this will occur if the atom or group of atoms contain electronegative elements. In NO3-, there are 3 oxygen atoms, all of which electronegative and so can stabilize the negative charge; and in HSO4- there are four oxygen atoms to stabilize the negative charge. If we didn't have these oxygen atoms, these anions would be nowhere near as stable, and these wouldn't be strong acids. [slide 6] In the case of hydrochloric acid, electronegativity alone doesn't explain the acidity, since the electronegativity of chlorine similar to that of oxygen. Therefore we would expect the negative charge to be equally stabilized by the oxygen atom in OH- as the Cl- ion. However, we know that OH- and H+ do react together to form a covalent bond, where as H+ and Cl- does not. The explanation here is that the new bond formed by oxygen and hydrogen is short and strong, whereas that for H-Cl is longer and weaker, due to the fact that chlorine is a bigger atom. Therefore, in solution, the H-Cl bond does not form, and the H+ and Cl- remain as ions. [slide 7] We see this trend down group seven. As the atoms get bigger, the bonds get longer and weaker, and therefore the hydrogen-halogen bond breaks into ions more readily, making the compounds more acidic. [slide 8] To summarise this, Strong acids occur when the negative ion stabilizes the negative charge more than HO- can. This occurs when there are enough electronegative atoms around, usually oxygen. In these cases, the anions do not form covalent bonds with H+, but remain as ionic solutions. Therefore these solutions contain the H+ ion, making it acidic, and a neutral anion which has stabilized the negative charge. In other cases, a negatively charged non-metal species will readily react with H+ to form a strong covalent bond. This occurs when the electrons on the anion are not so stabilized as in OH-, which would occur for less electronegative elements such as nitrogen, sulphur and carbon. [assessment slides] OK, here are some puzzles on this topic for you to have a think about.
Views: 8513 jamesmungall
In this video you will learn about the second type of strong bond between atoms, and the only other type of chemical bond, covalent bonds. Covalent bonds attach atoms together as molecules that share pairs of electrons. They almost always form between atoms of nonmetals. Because the electrons are tied up in pairs between atoms, covalent substances do not conduct electricity. Also, because the molecules are individual units all on their own, while the atoms in the molecules are bonded together tightly within, the actual molecules usually don't bond to other molecules very tightly. This results in covalent substances usually having lower melting and boiling points.
Views: 341 MrZ PhySci
Covalent Bonds, Hydrogen Bonds Instructor: Graham Walker View the complete course: http://ocw.mit.edu/7-01SCF11 License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu
Views: 30306 MIT OpenCourseWare
Learn the basics about covalent bonds, when learning about properties of matter. When similar atoms react, like non-metals combining with other non-metals, they share electrons. This is covalent bonding. Non-metals have shells of electrons that are normally half or more than half full of electrons. Since they have a strong attraction for a few additional electrons, it is energetically unfavourable for any of them to lose electrons, so they share electrons by overlapping orbitals. This makes a bonding orbital, or covalent bond, that contains two or more electrons. Covalent bonds can be represented by a dot and cross diagram. These diagrams show only the valence electrons. Covalent bonds are directional, which means they are in a fixed position. The overlap between orbitals mean that the atoms in covalent bonds are very close, and make covalent bonds strong. There are two kinds of covalent structure - small molecules, like water, and giant compounds, like diamond. The electrons in the bonds are evenly shared, which means the bonds are not polarised; there is little attraction between molecules, and forces between molecules are weak. Compounds made from small covalent molecules have low melting and boiling points and are volatile. They also don’t conduct electricity. Carbon and silicon tend to form giant covalent compounds. These bond in the same way, but instead of forming small molecules with one or two bonds, they form four, make up huge lattices or chains of many many linked up atoms. Diamond is a common example, and is made up of Carbon. These compounds have very high melting and boiling points because you have to break covalent bonds rather than intermolecular forces to make them free enough to act like liquids or gases. The covalent bonds hold them rigidly in place in the giant lattice. SUBSCRIBE to the Fuse School YouTube channel for many more educational videos. Our teachers and animators come together to make fun & easy-to-understand videos in Chemistry, Biology, Physics, Maths & ICT. JOIN our platform at www.fuseschool.org This video is part of 'Chemistry for All' - a Chemistry Education project by our Charity Fuse Foundation - the organisation behind The Fuse School. These videos can be used in a flipped classroom model or as a revision aid. Find our other Chemistry videos here: https://www.youtube.com/playlist?list=PLW0gavSzhMlReKGMVfUt6YuNQsO0bqSMV Twitter: https://twitter.com/fuseSchool Access a deeper Learning Experience in the Fuse School platform and app: www.fuseschool.org Follow us: http://www.youtube.com/fuseschool Friend us: http://www.facebook.com/fuseschool This Open Educational Resource is free of charge, under a Creative Commons License: Attribution-NonCommercial CC BY-NC ( View License Deed: http://creativecommons.org/licenses/by-nc/4.0/ ). You are allowed to download the video for nonprofit, educational use. If you would like to modify the video, please contact us: [email protected]
Views: 74032 FuseSchool - Global Education
This organic chemistry video tutorial explains how to determine which bond is more polar. It also explains how to rank the bonds from least polar to most polar. Subscribe: https://www.youtube.com/channel/UCEWpbFLzoYGPfuWUMFPSaoA?sub_confirmation=1 Access to Premium Videos: https://www.patreon.com/MathScienceTutor https://www.facebook.com/MathScienceTutoring/ New Organic Chemistry Playlist https://www.youtube.com/watch?v=6unef5Hz6SU&index=1&list=PL0o_zxa4K1BXP7TUO7656wg0uF1xYnwgm&t=0s
Views: 28324 The Organic Chemistry Tutor
A short video on surface tension for Ms. Allen's class. Script: Surface Tension really quick. Basically in a liquid molecules bond to the molecules around them. But liquid molecules don’t bond to air. So, instead of having to bond to liquid above it, the top layer can just double up on bonds, making a way stronger surface. Liquids with hydrogen bonds (such as water) can do this way better. This causes a bunch of cool things to happen. For example, when you fill up a cup with water, you can fill over the edge without the water spilling out. Or if you’re really light, like a water bug, you can walk on this surface. However, this also causes a number of not cool things to happen. Surface tension is the reason belly flops hurt, which is fine, but it’s also the reason that plane crashes in water are deadly. It essentially makes a liquid more like a solid wall at high velocities, creating danger in a range of areas. Surface tension can be broken by movement, too. You can see this in the white parts of waves, or in pools where ski jumpers practice. In summary, surface tension creates strong bonds in the top layer of a liquid. That’s all you need to know about surface tension.
Views: 58 Max Riley
Why water looks like.. ? Amazing slow-motion record This strong electrostatic attraction between Hydrogen atoms on one water molecule, to Oxygen atom on another, is called Hydrogen Bonding, or H-bonds. Further infos: graphene-lda.com/deep-dive-into-technology/full-container-inspection/fill-level-inspection/high-frequency/index.html see here:http://vimeo.com/92398561 CC by Attribution Adapted, mixed and commented by Graphene® on footage created by Don Whitaker and Chris Pantel. CC by Attribution -------------------------------------------------------------------------------------------- Thanks for Watching -------------------------------------------------------------------------------------------- Subscribe: https://www.youtube.com/user/iHostmiplay
Views: 29 Espra Tomsen