CHEMISTRY COMMUNITY

Joe Rich 1D

When calculating the pH of a buffer solution containing a weak acid/base and its salt, we are making the assumption that the initial concentrations of the acid/base and its respective ion (which is supplied initially by the salt) does not change. This means we are assuming that protonation and depro...

Joe Rich 1D

Why are we not able to use an icebox when calculating the concentration of H3O+ in a buffer solution of a weak base and its salt?

Joe Rich 1D

When drawing resonance structures for SO2, we see that there are two structures where one O has a single bond and one has a double bond, and a third (most stable) structure where both O atoms get a double bond and S keeps its lone pair of electrons. How would this double bond look in terms of sigma/...

Joe Rich 1D

Thank you guys!

Joe Rich 1D

If a ligand has an atom with 2 pairs of lone electrons (like H2O), why is it not able to donate both pairs of electrons to the central atom? Is it possible for a double or triple bond to be formed in a complex between a central atom and an atom in the ligand?

Joe Rich 1D

When atoms forms molecules, do all electrons become delocalized over the entire molecule, or only the electrons involved in resonance pi bonds? The book mentions that the resonance of the benzene molecule results in the electrons from the C=C double bonds to delocalized over the whole molecule, but ...

Joe Rich 1D

Heres a list of what I believe is the number of binding sites that each polydentate ligand forms. If there's anything I left out or got incorrect, I'd really appreciate any feedback!

En: 2
Dien: 3
Nitrito: 1 (sometimes 2)
Carbonato: 1 (sometimes 2)
Ox: 2
Sulfato: 1 (sometimes 2)
EDTA: 6
Porphyrin: 4

Joe Rich 1D

Chemical equilibrium can occur for any chemical reaction, whatever phase the reactants and products are in. Chemical equilibrium only means that the amount of reactants and products are not changing anymore, so this can occur for compounds in any state. When we calculate the equilibrium constant, th...

Joe Rich 1D

What's the difference between a free radical and an ion? Would Cl existing by itself be considered to have a free radical because there is only one electron in its pz orbital? Or would N existing by itself have 3 free radicals because each electron in each p orbital exists by itself?

Joe Rich 1D

So we learned about monodentate ligands with only one atom possessing a lone pair of electrons (i.e. Cl-) and polydentate ligands which have multiple atoms with a lone pair of electrons (ie. oxalato). But without seeing a picture or molecular formula for a molecule, how do we know what type of polyd...

Joe Rich 1D

The answer for question 4.57 says that a higher electronegativity for an atom makes its orbitals have lower energy. Why is that?

Joe Rich 1D

What is the specific wording that will be used to distinguish from the arrangement of electrons around a central atom versus the name we give it? For instance, a AX2E2 molecule has an arrangement of tetrahedral and the name bent.

Joe Rich 1D

A photon checks into a hotel and is asked if he needs any help with his luggage. He says, "No, I'm traveling light."

Joe Rich 1D

If you're not part of the solution, you're part of the precipitate.

Joe Rich 1D

Hey! I like to remember trends by thinking of how a trend changes as you move up and to the right of the periodic table. Atomic radius and ionic radius are the biggest in the bottom left (at Cesium), and generally decrease as you move up and to the right. Ionization Energy, Electron Affinity, and El...

Joe Rich 1D

Why does SO2 have 3 resonance structures (one where each oxygen has a double bond, and the others where one oxygen has a double bond and one has a single bond - pg 85 of the course reader) if the first structure has 10 electrons around sulfur and the other structures only have 8 electrons around the...

Joe Rich 1D

Why is the energy of an electron negative for any given energy level (according to the equation E=-hR/(n^2))? What does the energy for an electron at a given energy level correspond to (for instance, does a higher energy of an electron change its velocity or wavelength)?

Joe Rich 1D

Thank you so much!

Joe Rich 1D

How does Effective Nuclear Charge (Zeff) affect the energy of an electron?

Joe Rich 1D

Thank you guys so much! Just to make sure I generally understand how it works, here's my overall summary of the equation: The Hamiltonian Operator is defined as the sum of the kinetic energy (which is derived mathematically) and the potential energy (which is determined depending on the system being...

Joe Rich 1D

What are the steps we need to take to obtain the wave function using Schrodinger's Equation? How are we able to figure out the potential energy function for an electron, and why does taking the double derivative of the wave function help us obtain kinetic energy?

Joe Rich 1D

I just wanted to clarify the meaning and application of particle in a box. Is the idea of particle in a box to show that a particle of mass m that is constrained by 2 one-dimensional barriers can only have certain wavelengths, which means that particles have quantized energy levels?

Joe Rich 1D

Hi! My understanding is that orbitals were created because of the wave-like properties of electrons, because the wave-like properties of electrons means their exact positions cannot be known exactly. Wave functions are created mathematically to represent probability density of finding electrons in c...

Joe Rich 1D

I was wondering if you could use the same type of equation as you do for light to relate energy and wavelength, which is E=hc/λ. But instead of using the speed of light, I would substitute in the velocity of the particle. I wasn't sure whether this was a valid technique or not though.

Joe Rich 1D

So we can calculate the wavelength of an electron (or any other particle) using De Broglie's Equation, λ=h/p. But is there a way to calculate the frequency of these waves, or do we even need to know how to do this at all?

Joe Rich 1D

De Broglie's Equation is λ=h/p, where p=mass x velocity. To calculate the wavelength of an electron, we can plug in the (given) velocity of the electron and the mass of an electron into De Broglie's Equation. The mass of an electron is a constant (9.11E-31 kg). We want the mass in kg because h is gi...

Joe Rich 1D

You can also think about it in terms of the way the shape of the wave changes as frequency decreases. If frequency goes, down, this means wavelength goes up, and the wave of light flattens. The wave of light actually describes the oscillation of the electric and magnetic fields as light travels thro...

Joe Rich 1D

We utilize the formula E=hc/λ if we are given the wavelength of light and want to solve for the energy per photon of the light (or if we are given the energy per photon of the light and want to calculate the wavelength). This equation is really just combining the two equations c=λν and E=hν in order...

Joe Rich 1D

Part a actually does ask for the wavelength of the electron I think.

Joe Rich 1D

The question asks for the wavelength of an electron that was ejected from a metal surface with a velocity of 3.6 x 10^-3 km/s. I know that one way to solve this is by using the De Broglie equation, but I was just wondering if it was possible to solve this by solving for Kinetic Energy of the electro...

Joe Rich 1D

It should also be said that the question in the post-assessment asks for the energy required to remove 1 electron, but the work function is given in kJ per mol of electrons. In order to convert this number into the energy (in Joules) to remove a single electron, we first multiply 150.6 kJ by 1000 to...

Joe Rich 1D

The answer key actually appears to be slightly off with its molar ratio, but the answer still comes out the same. The book divides 0.0924 mmol C by 0.0113 mmol N to get a molar ratio of 8.18C:1N, but this is because they rounded off before finishing their calculations. Without rounding off, the mola...

CHEMISTRY COMMUNITY

Search found 32 matches

Re: Icebox for Buffers?

Icebox for Buffers?

Double Bonds in SO2

Re: Polydentates

Polydentates

Delocalization

List of Polydentates

Re: Chemical Equilibrium

Difference between Free Radical and Ion

Polydentates

Relationship between Electronegativity and Orbital Energy

Naming Compounds

Re: Post All Chemistry Jokes Here

Re: Post All Chemistry Jokes Here

Re: Electron Affinity

SO2 Resonance [ENDORSED]

Energy of an Electron

Re: Question about Effective Nuclear Charge

Question about Effective Nuclear Charge

Re: Obtaining the Wave Function

Obtaining the Wave Function

Conceptualizing Particle in a Box

Re: wave function and orbitals

Re: Question about 1.33

Frequency of an Electron?

Re: Class Lecture Work Example Question [ENDORSED]

Re: Quantum World 1.3

Re: Photoelectric Effect

Re: Question about 1.33

Question about 1.33

Re: energy required to remove an electron [ENDORSED]

Re: Difficulty with HW Question F.21 [ENDORSED]