CHEMISTRY COMMUNITY

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I think we might be asked to come up with the half reactions

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I don't think we would be asked that unless W was a perfect square or something like that... like if you were given W=16 you could say x^n=4^2

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I think so

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could someone explain to me how to find the units for the rate constant? Is the unit of the rate always moles per second?

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I think because the rate has to be mol.L^-1.s^-1 then the rate constant has to have the same units because it's not multiplied by anything

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How do we know the manganese in MnO4- has a charge of +7? Why is the charge of O4 8-?

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water vapor burns more than water at 100 degrees celsius (boiling temperature) because a lot of energy is needed to break the intermolecular bonds between the water molecules so that the water is vaporized. This means that when it came in contact with your skin it would release all that extra energy...

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I think the whole point of the calorimeter is to have a reaction that doesn't lose energy or matter as it happens, so it basically isolates heat and doesn't release any gases produced in the reaction. I don't understand what the bomb calorimeter is exactly either though.

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I think it depends on what values are given in the problem. But also I think Hess's law is more accurate than bond and standard enthalpies so if you can do either I would do Hess's

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R is specific to each gas, it is a constant that is given

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If you are given the energy of a labor and its wavelength how do you calculate the number of photons?

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If what you mean is that you can divide or multiply on either side by the same thing then yes

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On the midterm it says for an atom with the quantum number n=9 so this implies l has to be smaller than 9, the lowest ml would be -8

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They work for other molecules as well (if you have a molecule with a Nitrogen with a lone pair and a carboxyl group for example it would be amphiprotic)

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I think it's less than 90

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I think saying H+(aq) or H3O+ is the same because saying H+ is in aqueous solution means it will bind with H2O molecules to produce H3O+

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pH decreases when [H+] increases because H+ is what makes a solution acidic. [H+] increasing is the same as saying [H3O+] is increasing and pH=-log[H3O+]

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there would be one sigma and two pi

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I understood that we have to know sigma and pi bonds and hybridization but not the hybridization specific to each bond. So we might have to say the hybridization of an atom but we won't have to know if the bond is C2sp3 or C2p
I'm still not 100% sure

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I think it's because the difference in electronegativity between carbon and oxygen is bigger than that of carbon and carbon or carbon and nitrogen

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I think it's because for it to be considered a proton transfer it really has to be just the proton that changes places and in this case it's rather NH that is substituting the oxygen (which then bonds with the H2 produced)

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Also you can see it as H3O+ and H+(aq) which are equivalent because H3O+ is just H2O + H+

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So just to be clear the test won’t cover anything from Monday’s lecture? Like coordination compounds?

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Can someone explain why H2O has a higher melting and boiling temperature than H2S please? I get that it’s because of hudrogen bonds but wouldn’t H2S have the same hydrogen bonds as H2O has?

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Also depending on wether the molecule is Cis or trans affects the way it will react with other molecules

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a cis molecule is axially symmetrical and a trans molecule is diagonally symmetrical. If you have a C2Cl2H2 you can have H2C=CCl2 (cis) or HClC=CClH (trans)

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not necessarily, because a water molecule is polar even though it is neutral; I think it depends on the electronegativity of the atoms in the molecule

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because according to the VSEPR model that molecule is AX3E2 wich is T shape. If it helps think that the central atom has 5 electron density regions so the shape would be trigonal bipyramidal if all 5 were bonds but in this case you replace two of those with lone pairs and it gives yo the T shape.

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I'm not certain but I would think that the sigma bond would break first given that the bond is weaker

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I think it's also important to understand how strong electron repulsion is depending on wether it's a bonding electron or a lone pair electron

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sigma bonds are a single bond and pi bonds are a double bond

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Could someone rephrase Hund's rule, and explain the difference between Hund's and Pauli's

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I saw a question that asked what element with a 2+ charge would have this ground state electron configuration:
[Ar]4d10
and the answer is cadmium, but i don't understand why.

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Why are s-block metals typically more reactive than p-block metals?

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I remember the professor saying the test went up to Friday’s lecture. It’s is only on the topics in The Quantum World

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Will the equations be given? Such as the Schrödinger’s equation or Heisenberg’s indeterminacy equation?

CHEMISTRY COMMUNITY

Search found 36 matches

Re: Cell Diagram Half Reactions

Re: Calculating the Number of Orientations Mathematically

Re: example

Rate constant units

Re: Unit for rate constant for zeroth-order reaction

MnO4-

Re: Steam resulting in burns?

Re: calorimeter

Re: When to use which method for calculating reaction enthalpies

Re: value of R?

Number of photons

Re: heisenberg's

Re: Why is this statement incorrect?

Re: Amphoteric with H+

Re: T-shaped structures

Re: H+ vs H3O+

Re: pH

Re: pi and sigma bonds

Re: Sigma and pi bonds

Re: Double bond lengths

Re: 7th edition 6A.9 Part C

Re: H30+ and H+

Re: Test 3 Content

Boiling temperatures and hydrogen bonds

Re: Cis and Trans

Re: Cis and Trans

Re: Polar Molecule

Re: Lone Pairs

Re: Pi Strength

Re: Bond angles

Re: sigma and pi bonds

Hund's rule vs Pauli's

cadmium ground state electron configuration

Properties of metal

Re: Test 2

Exam 2