CHEMISTRY COMMUNITY

ahuang

clean coal produces less So2 (less sulphurous acid thus less acid is reacting with water vapor to form acid rain)

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Is trigonal planar polar if one of the attached atoms is different from the other two? Is it similar to how tetrahedral is only nonpolar if all four attached atoms are the same?

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I understand that you use a single arrow in an equation to show when a strong acid or base completely dissociates in water, but does that mean you use double arrows for everything that is not a strong acid or base? In the homework, none of the equations used double arrows. Would we be penalized on t...

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Why do protons not bond to the oxygens? Aren't there two lone pairs on oxygen that two hydrogens can bond to?

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How do you know if a ligand can be polydentate? I know that the metal can bond to the lone pairs but for example in Oxalate (C2O4 2-), it can be bidentate, but why is it not tetradentate?

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A good list to know is this list of 7 strong acids: HCl, HBr, HI, H2SO4, HNO3, HClO3, HClO4 Also know that generally molecules with COOH are weak acids. is H2SO4 different from the others because it has two Hydrogens? It's different in that H2SO4 can dissociate twice, meaning it is polyprotic: H2SO...

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Stronger acids would make weak bases because of its conjugate and vice versa.

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A good list to know is this list of 7 strong acids: HCl, HBr, HI, H2SO4, HNO3, HClO3, HClO4
Also know that generally molecules with COOH are weak acids.

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BeylemZ-4A wrote:would a really weak base be close to 7? or as far away from 7 as possible?

for example:
would a pH of 8 be more or less basic than a pH of 12?

a pH of 8 would be less basic than a pH of 12.

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I understand the definition of amphoteric compounds, but how do you identify them or do you have to memorize a list?

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It probably will because everything we have learned is connected and builds on top of each other.

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Bis- , tris- tetrakis-, pentakis- are used if the ligand has the same prefix as the polydentate so you wouldn't be using the prefix "di " twice to name a compound. The ligand would be named with di and then name the polydentate with "bis".

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Also, I think the difference between "ammine" and "amine" is that "ammine" is used when ammonia is acting as a ligand while "amine" is used when the compound formed ammonia by replacing hydrogen atoms with other hydrocarbons.

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Ethylene comes before the ammine because the ligand goes before the ion in naming.

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To find the oxidation state, you need to figure out the oxidation states of the other atoms in the molecule. For example in NiCl2, you know that each Cl is -1. Since the overall molecule has a neutral charge, Ni must be +2 to balance the two -1 for the Cl's.

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Carbonic Acid and Benzoic Acid are included in Bronsted acids because they are proton donors.

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I think it's first important to know that both transport O2 but myoglobin transports O2 in muscle cells and hemoglobin does so in blood. Also, Fe bound to porphyrin ligand makes up a heme complex and a heme complex bound to a protein makes up the myoglobin. Hemoglobin has 4 myoglobin like molecules,...

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AX2E follows trigonal planar where one of the bonds is a lone pair, thus the angles are less than 120 degrees.

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I think we do.

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Do we have to know T shaped because it is in the homework, but we did not go over it in class

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Typically shapes like bent or trigonal pyramidal have slightly less than a typical tetrahedral bond angle due to the number of electron pairs on the central atom.

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The formula for seesaw is AX4E where there are 4 bonds and one lone pair. The bond from trigonal bipyramidal that is selected as a lone pair must be on the equitorial plane so there is less repulsion, making it more stable.

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You can tell if it is polar by electronegativity. If an atom has more electronegativity than the other, it will be partially negative, pulling electrons towards it, leaving the other atom partially positive

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Is the dispersion force just within the atom or is it also found between two atoms?

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Will Test 2 just be on Molecular Shape and Structure? Will it be cumulative have questions from past topics like quantum world?

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Pentane is a mobile fluid because the bods are weak. Pentadecane is a viscous fluid similar to a thick oil, and Octadecane is a waxy solid. The picture showed a metal rod dipping into each fluid.

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The electrons are not being transferred or shared. Hydrogen bonding just shows the attraction between atoms

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Oxygen has lower electronegativity because it has an extra electron added to a half full orbital, creating electron-electron repulsion.

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First draw out the lewis structure for each example and compare bond lengths with single, double, or triple bonds. A triple bond has the strongest and shortest bond length while a single bond has the weakest and longest bond length.

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Cl and O are single bonded and oxygen must follow the octet rule, so that's why Cl must be a radical

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For question 2.7, when I drew the lewis structure for the N5+ cation, it had alternating single and double bonds, where each of the N atoms had 5 electrons except one (one 1+ formal charge). However, when I looked up the structure, it actually had 2 triple bonds and 2 single bonds with two 1+ formal...

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When determining whether which compound has bonds with greater ionic character, do you use the difference in electronegativity between the atoms? If so, how can you tell if C-O electronegativity difference is greater than that of C-S?

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Besides doing practice problems, I like to retake my notes again even though it is time consuming. This way, I can understand and remember the conceptual parts of the topics better.

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The sizes of the two lobes of the p orbitals are different sizes, so px, py, and pz are different

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Why are compounds with resonance structures more stable?

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The d orbitals can accommodate the extra valence electrons

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Amy Luu 3L wrote:I'm confused on part d of the problem. Why is hydrogen telluride H₂Te? I don't know how to get this since i thought hydrogen would want to gain an electron so it would also be an anion?

Telluride has a 2-, so it would need two Hydrogens since each Hydrogen has a 1+ charge.

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Pauli Exclusion Principle simply states that in each orbital there are two electrons with opposite spin. Hund's rule states that each orbital should be filled up once before the second electron is added. It's also known as "the bus seat rule". On a bus, you want to maximize the seating so ...

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Molecular spectroscopy can be used to identify molecules, since each element has a certain pattern like a fingerprint.

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Does anyone know when we will be receiving our tests back?

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The detector is a machine that detects the speed of the particle. This will allow us to calculate other measures like de Broglie wavelength.

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To find the number of orbitals in a subshell using l, there is a formula:
# orbitals = 2l + 1

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Planck's Constant is used in the following equations:
E=hv (Energy = h * frequency)
E = (-hR)/n^2 (Energy = (-hR)/(energy level)^2

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If carbon is in the molecule, it is usually written first, and hydrogen is second. For now, I think we just need to know that hydrogen and metals come first and nonmetals are second.

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Balancing charges are used in balancing redox equations, so I don't think we need to worry about that yet.

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For the upcoming test on Tuesday, will we be penalized for having incorrect sig figs?

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In the lecture slides, it said that an electron's wavelength is around 10^-12m. In the modules it asks if certain wavelengths are able to be detected. I just wanted to confirm that if the wavelength smaller than 10^-12, it is detectable. But how much smaller is detectable? Is ~10^-15m acceptable?

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First, you notice that there are 6N on the left and only 3N for products. Thus, multiply HN3 by 2. After, there are 2H for reactants and 4 for products. Therefore, multiply H2O by 2. This will finalize balancing the equation:
Mg(N3)2 + 2H2O -> Mg(OH)2 + 2HN3

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They experience particle and wave like properties as shown in the slit experiment. If it passes through the slits and hits the detector directly, it is behaving like a particle. However, if it forms a diffraction pattern, it is behaving like a wave - similar to what happens when an incident of light...

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You use kg and m because those are the SI units used in the formula.

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I don't think we have to know all the naming rules at the moment, but I think it would be useful to know some basics since they keep appearing in the homework: If the compound is ionic, you add an "ide" to the end (e.g. NaCl is sodium chloride) Useful Polyatomics: (NO3 nitrate, NO2 nitrite...

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Moles of solute do not change even when more solvent is added because there is no solute being added or removed. It is easier to think that when more solvent is added, it is being added to its surrounding so the solute and solvent are separate.

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