CHEMISTRY COMMUNITY

paulacamara1E

What exactly do we need to know regarding acid rain for the final? Thank you.

paulacamara1E

For the final, do we need to know how to calculate pOH, or just pH?

paulacamara1E

I was just wondering if we had to memorize the amphoteric oxides, or if there's a method of determining them using the periodic table?

paulacamara1E

So we are not supposed to know specifics? For example that cobalt has to do with vitamin B12 or that different transition metals like Mn, Ni, Cu and Zn have to do with different enzymes?

paulacamara1E

On my notes I have the sentence that says regions of electron density equal the number of hybrid orbitals. I copied it from Dr. Lavelle's powerpoint but I am having a hard time understanding this concept. Could someone further explain it in simple terms?

paulacamara1E

Can someone clarify how we would be tested on sigma and pi bonds, for example types of questions that could involve these bonds?

paulacamara1E

When a question asks which structure contributes more to resonance, what does that mean?

paulacamara1E

Professor Lavelle pointed out two different types of bonds in lecture, bond angles and just angles, could someone clarify that please? my notes confused me with the terms

paulacamara1E

Orher than knowing how to write the AXE notation are there any other ways we could be tested on this concept on the final?

paulacamara1E

Does it matter which name we use for Van der Waals? Like London, Dispersion, Induced dipole etc? And are they considered bonds or simply interactions?

paulacamara1E

I understand that when dipole moments cancel out, a molecule is not polar but I am having trouble understanding the dipole moments on the first place. Does anyone have a simple explanation that could help understanding dipole moments and their connection to polarity?

paulacamara1E

Can someone clarify until what lecture's material test 3 will cover? Should we focus on lewis structures and formal charge or should we also know bond strengths and lengths and dipole dipole interactions?

paulacamara1E

In the last lecture one of the TAs was explaining the concept of expanded octects in the elements of the 3rd row of the periodic table or below. The example that was given was with SO4. I do not really understand why double bonds were formed between the S and two of the Os to make it more stable but...

paulacamara1E

For this homework problem could someone explain what they mean by "shielding"?

paulacamara1E

I still don't understand letters b and d. For the explanation for letter d, what do you mean by "only one orbital can exist in that location in space"? If l=2 aren't there 5 orbitals (ml)? And doesn't n=3 and l=2 refer to row 3 in the d block? Thank you and sorry if the questions are confu...

paulacamara1E

On the practice review that one of the UA's prepared, the last question (number 9) is about molarity and volume. Since M is mol/L I assumed that we had to convert the given volume from mL to L, however, that is not the case. All of the calculations are made with mL, why is that so? And how do I know...

paulacamara1E

When reviewing the photoelectric effect for the midterm I remembered that one of the surprising outcomes of the experiment was that increasing intensity did not make a difference in the removal of electrons. I do understand that what matters is the energy of the photon, I was just wondering what int...

paulacamara1E

This might be a simple question but I am having a really hard time differentiation energy levels and orbitals. When I say energy levels I mean what we studied for test 2, like n=2 or n=1 (Balmer and Lyman series material). How do orbitals (s, p, d and f) connect back to that?

paulacamara1E

Dr. Lavelle explained the concept of nodal planes during lecture but I was reviewing my notes and got quite confused. Can someone further explain this concept and what is its importance when it comes to orbitals and s orbitals not having them?

paulacamara1E

I'm also confused as to why dividing 64J by 4.7x10^-19J/photon instead of the other way around.
Other than that, on the last part that asks us to find moles of photons, why use Avogadro's number as the number of photons in 1 mole?

paulacamara1E

Why is the power of the final answer -19? I keep getting a different result every time I repeat the calculation.

paulacamara1E

Why does energy decrease when wavelength increase? My TA explained the concept in discussion but I don't think I fully got it.

paulacamara1E

I am quite confused with the uncertainty in position in problems referring to Heinsberg's Indeterminacy Equation. I understand how to apply the formulas but why its the uncertainty in position equals to the diameter of the atom?

paulacamara1E

When discussing atomic spectra and energy levels why is the gap between n1 and n2 the biggest?

paulacamara1E

Can someone further explain the statement presented in lecture that says, "unless E(photon)>or=E(energy remove e-) then e- not emitted even for high intensity light"?

paulacamara1E

Dr. Lavelle mentioned that drawing a simple diagram helps when solving problems regarding the photoelectric effect. Drawing the diagram has indeed helped me with the problems, I was just wondering what DET stands for located on the top right corner on the diagram used in class?

paulacamara1E

When reviewing the properties of light Dr. Lavelle gave as the constant c as 3.00 x 10ˆ8 m/s. I understand that this constant will always be given and that it is part of a formula but I was quite confused as to which type of problem/when would we use this constant?

paulacamara1E

When given a visual representation of a molecule it is possible to write both its empirical and molecular formulas, however, I am having a bit of confusion when it comes to doing so. Is it correct to count the number of elements for the molecular formula? What about the empirical formula?

paulacamara1E

When it comes to equations in quantum mechanics, Dr. Lavelle mentioned that a key concept is that their variables are quantisized or discrete. Could someone further elaborate what he means by a quantisized or discrete variable?

paulacamara1E

When going over problem G21 I was quite confused why after finding the number of moles for K2S we have to multiply by 2molK+/1molK2S? I figured it might be because there are two K but I don't really understand why multiply. Can someone explain?

CHEMISTRY COMMUNITY

Search found 30 matches

Acid Rain [ENDORSED]

pOH

Amphoteric Oxides

Re: Biological Function on Final?

Hybrid orbitals

Sigma and Pi bonds

Resonance [ENDORSED]

Difference in angles

Re: AXE Notation and Shape

Van der Waals [ENDORSED]

Dipole moments

Test 3

Expanded Octet

Homework problem 2.37

Re: 2.29

#9 on Midterm Practice Review (unicorn)

Intensity of Photon

Energy levels and Orbitals

Nodal Planes

Re: 1.27: Units Confusion

Homework number 1.25a [ENDORSED]

Wavelength/frequency

Atom's diameter

Energy levels

E(photon)>or=E(energy remove e-) [ENDORSED]

Photoelectric Effect Diagram [ENDORSED]

Speed of light constant

Determining Formulas Based on Molecule

Equations in Quantum Mechanics [ENDORSED]

Fundamentals G21