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This is a Videoscribe tutorial on how to draw Lewis structures of molecules. This is my second tutorial in the series. The first video includes Lewis diagrams of atoms and can be found here: https://youtu.be/cIuXl7o6mAw Lewis diagrams (aka Lewis structures, Lewis dot structures, Lewis dot diagrams) are useful because they use simple drawings to show how atoms share valence electrons in molecules, polyatomic ions, and other covalent structures. This video: 1) reviews the 5 basic steps for creating a Lewis structure 2) goes through 4 detailed examples 3) identifies patterns of bonding to help create Lewis structures 4) introduces a faster way to draw Lewis structures 5) demonstrates how this trick works or falls short for 4 additional detailed examples
Video by Business Insider - http://www.businessinsider.com/gallium-safe-metal-liquid-mercury-2016-5 ...Music: Flying Dream by Dhruva Aliman - https://dhruvaaliman.bandcamp.com/ ...Gallium is a chemical element with symbol Ga and atomic number 31. It is in group 13 of the periodic table, and thus has similarities to the other metals of the group, aluminium, indium, and thallium. Gallium does not occur as a free element in nature, but as gallium(III) compounds in trace amounts in zinc ores and in bauxite. Elemental gallium is a soft, silvery blue metal at standard temperature and pressure, a brittle solid at low temperatures, and a liquid at temperatures greater than 29.76 °C (85.57 °F) (slightly above room temperature). The melting point of gallium is used as a temperature reference point. The alloy galinstan (68.5% gallium, 21.5% indium, and 10% tin) has an even lower melting point of −19 °C (−2 °F), well below the freezing point of water. Since its discovery in 1875, gallium has been used to make alloys with low melting points. It is also used in semiconductors as a dopant in semiconductor substrates. Gallium is predominantly used in electronics. Gallium arsenide, the primary chemical compound of gallium in electronics, is used in microwave circuits, high-speed switching circuits, and infrared circuits. Semiconductive gallium nitride and indium gallium nitride produce blue and violet light-emitting diodes (LEDs) and diode lasers. Gallium is also used in the production of artificial gadolinium gallium garnet for jewelry. Gallium has no known natural role in biology. Gallium(III) behaves in a similar manner to ferric salts in biological systems, and has been used in some medical applications, including pharmaceuticals and radiopharmaceuticals. Gallium is used in thermometers as a non-toxic and environmentally friendly alternative to mercury and can withstand higher temperatures than mercury. In 1871, the existence of gallium was first predicted by Russian chemist Dmitri Mendeleev, who named it "eka-aluminium" from its position in his periodic table. He also predicted several properties of eka-aluminium that correspond closely to the real properties of gallium, such as its density, melting point, oxide character and bonding in chloride. Mendeleev further predicted that eka-aluminium would be discovered by means of the spectroscope, and that metallic eka-aluminium would dissolve slowly in both acids and alkalis and would not react with air. He also predicted that M2O3 would dissolve in acids to give MX3 salts, that eka-aluminium salts would form basic salts, that eka-aluminium sulfate should form alums, and that anhydrous MCl3 should have a greater volatility than ZnCl2: all of these predictions turned out to be true. Gallium was discovered using spectroscopy by French chemist Paul Emile Lecoq de Boisbaudran in 1875 from its characteristic spectrum (two violet lines) in a sample of sphalerite. Later that year, Lecoq obtained the free metal by electrolysis of the hydroxide in potassium hydroxide solution. He named the element "gallia", from Latin Gallia meaning Gaul, after his native land of France. It was later claimed that, in one of those multilingual puns so beloved by men of science in the 19th century, he had also named gallium after himself: "Le coq" is French for "the rooster" and the Latin word for "rooster" is "gallus". In an 1877 article, Lecoq denied this conjecture. Originally, de Boisbaudran determined the density of gallium as 4.7 g/cm3, the only property that failed to match Mendeleev's predictions; Mendeleev then wrote to him and suggested that he should remeasure the density, and de Boisbaudran then obtained the correct value of 5.9 g/cm3, that Mendeleev had predicted almost exactly. From its discovery in 1875 until the era of semiconductors, the primary uses of gallium were high-temperature thermometrics and metal alloys with unusual properties of stability or ease of melting (some such being liquid at room temperature). The development of gallium arsenide as a direct band gap semiconductor in the 1960s ushered in the most important stage in the applications of gallium. Elemental gallium is not found in nature, but it is easily obtained by smelting. Very pure gallium metal has a silvery color and its solid metal fractures conchoidally like glass. Gallium liquid expands by 3.1% when it solidifies; therefore, it should not be stored in glass or metal containers because the container may rupture when the gallium changes state. Gallium shares the higher-density liquid state with a short list of other materials that includes water, silicon, germanium, antimony, bismuth, and plutonium. Music: Flying Dream by Dhruva Aliman https://dhruvaaliman.bandcamp.com/ http://www.dhruvaaliman.com/ Spotify - https://open.spotify.com/artist/5XiFCr9iBKE6Cupltgnlet
---- Balancing Chemical Equations in Five Easy Steps --- Balancing chemical equations is a core skill in chemistry. In this video you'll learn the basics for balancing equation with examples and explanation. Get more chemistry help at www.Breslyn.org. There are three key things to remember when balancing reactions. - First count the number of each type of atom on each side of the chemical equation. It helps to make a table below the equation to be sure you have the correct numbers. - You can only change the coefficients (these are the numbers in front substances). - You should NOT change the subscripts (the small numbers after elements). That would make a new chemical compound! Once you're done balancing a chemical equation double check both sides to be sure you have the same number of each type of atom on each side of the balanced equation. --- Drawing done captured with Camtasia Studio. Audio recording using a Yeti Blue microphone.
- Get familiar with the periodic table -CATions are (pawsitive) and anions are negative - Ionic: Cation + anion (-ide) NaCl : sodium chlorIDE Mg3N2: Magnesium nitrIDE K2O: potassium oxIDE TRANSITION METALS (same as ionic, but with roman numerals) CuCl: copper (I) chloride CuCl2: copper (II) chloride Hg2Cl2: mercury (I) chloride HgO: mercury (II) oxide ***Note that I made a mistake in the video FeS: Iron (II) sulfide Fe3S2: iron (III) sulfide POLYATOMIC IONS NH4+ Ammonium 1- charge: BrO3 Bromate ClO3 chlorate ClO2 chlorite CN cyanide HSO4 hydrogen sulfate OH hydroxide ClO hypochlorate NO3 nitrate NO2 nitrite ClO4 perchlorate MnO4 permanganate SCN thyocyanate 2- charge: SO4 sulfate SO3 sulfite CO3 carbonate CrO4 chromate Cr2O7 dichromate 3- charge: PO4 phosphate PO3 phosphite Examples: NH4Cl : Ammonium chloride BaCO3: barium carbonate sodium chlorite: NaClO2 Lithium sulfite: Li2SO3 sodium perchlorate: NaClO4
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! Subscribe: http://bit.ly/ProfDaveSubscribe ProfessorDaveExplains@gmail.com 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
A step-by-step explanation of how to draw the BaS Lewis Dot Structure.
For BaS we have an ionic compound and we need to take that into account when we draw the Lewis Structure. We’ll first draw the metal and put it in brackets with its charge on the outside (video: finding ionic charge: https://youtu.be/M22YQ1hHhEY).
Next, we'll draw the Lewis Structure for the S 2- ion and add brackets. We put the two ions together to complete the Lewis structure for BaS. Note that BaS is also called Barium sulfide.
For a complete tutorial on drawing Lewis Structures, see my video: https://youtu.be/1ZlnzyHahvo
For more practice, see https://youtu.be/DQclmBeIKTc
To learn to find the valence electrons: https://youtu.be/VBp7mKdcrDk
Note that is it more common to draw Lewis Structures for covalent (molecular) compounds where valance electrons are shared. In the case of ionic compounds, where we have a metal bonded to a non-metal (or group of non-metals), the Lewis diagram represents a formula unit. Many of these formula units make up a crystal lattice. So when we talk about the structure for BaS we think of it together with other BaS formula units in a crystal (NaCl is a good example of this: https://en.wikipedia.org/wiki/Sodium_chloride).
Get more chemistry help at http://www.thegeoexchange.org/chemistry/bonding
Drawing/writing done in InkScape. Screen capture done with Camtasia Studio 4.0. Done on a Dell Dimension laptop computer with a Wacom digital tablet (Bamboo).