CHEMISTRY COMMUNITY

Rebecca Chu 1C

How do you find the charge on ligands and the oxidation # if you're only given the overall charge of the molecule. I thought you needed to know both the overall charge and charge on all ligands to find the oxidation #.

Rebecca Chu 1C

It asks to circle which compound has the highest ionic character and the compounds were KBr or NaBr. Why does KBr have a more ionic character than NaBr? I circled NaBr because I thought Na has a higher electronegativity than K so NaBr has a higher ionic character, but I got it wrong.

Rebecca Chu 1C

I know 4 ligands can either be a tetrahedron or square planar, but how am I supposed to tell which shape is which when there are 4 ligands?

Rebecca Chu 1C

Why doesn't the central atom follow the octet rule though?

Rebecca Chu 1C

This is a question from test 3. What would the correct lewis structure for a phosphate molecule be?

Rebecca Chu 1C

How do I tell whether an atom in a molecule has a partial positive/negative charge or a full positive/negative charge?

Rebecca Chu 1C

You look at the size of the atoms. Smaller atoms that have small radius (and in turn, shorter bond length) will have a stronger bond and therefore, be shorter. And if one of the molecules has resonance structures, the double bond would be longer on the molecule with resonance structures.

Rebecca Chu 1C

Does the central atom have to follow the octet rule? I noticed in some lewis structures the central atom doesn't always have an octet.

Rebecca Chu 1C

Vivian Gonzalez 1A wrote:A dipole is a separation of opposite electrical charges. The larger the difference in electronegativity, the greater the dipole moment.

So if there is a greater dipole moment, does the molecule have a stronger ionic bond? And is its potential energy greater?

Rebecca Chu 1C

My TA said there was a shortcut she uses for calculating formal charge. (I have Rosie.) Does anyone know what it is? I didn't write down the shortcut.

Rebecca Chu 1C

Okay so I know that ionic bonds exhibit covalent character, but what exactly is the covalent character that it exhibits? And what constitutes a bond with a "more covalent character" than another? Also, if an ionic bond exhibits a covalent character, how do I differentiate whether a bond is...

Rebecca Chu 1C

How am I supposed to distinguish a Lewis acid from a Lewis base if I'm given a molecule?

Rebecca Chu 1C

So is that specific only to the 3d and 4s orbitals or does the d subshell have lower energy than the s subshell that precedes it in general (i.e. will 4d have a higher energy level than 5s, etc.)?

Rebecca Chu 1C

When I asked my TA, she said the solutions usually aren't posted and you can just ask questions from the test on Chemistry Community.

Rebecca Chu 1C

An organic compound contains C and H so you know your empirical formula will be C_{x}H_{y} (because we don't know what x and y are yet). And then you are given grams of carbon dioxide which you can use to find the moles of C. You do the same thing with water (i.e. find moles of H) Basically: 69.4 g ...

Rebecca Chu 1C

What does it mean when 2 electrons are parallel? And what does it mean when 2 electrons are paired?

Rebecca Chu 1C

Difference between angular node and radial node?

Rebecca Chu 1C

I don't think atoms of different elements can have the same atomic radius so if the radius of an atom changes, you're probably dealing with a different atom that you initially were.

(NOT ENTIRELY SURE ABOUT THIS, BUT IF I AM WRONG, PLEASE CORRECT ME)

Rebecca Chu 1C

I hope this visual helps a little bit.

Rebecca Chu 1C

First, you have convert 4.37 eV to J so you have 4.37 eV x [(1.602 x 10^-19 J)/1 eV] = 7.0 x 10^-19 J. It also tells you that this is your work function so this is your \Phi You should also convert v = 1.5 x 10^3 km/s to 1.5 x 10^6 m/s since we will be working with Joules. Then you use KE = \frac{1}...

Rebecca Chu 1C

1 keV = 1.602 x 10^-16 J so you use dimensional analysis to convert keV to Joules.
140.511 keV x [(1.602 x 10^-16) J / 1 keV] = 2.251 x 10^-14

Rebecca Chu 1C

Why doesn't the photoelectric effect work in with high intensity light? Why must it be a light source with a long wavelength? What does a long wavelength do to the electrons that a short wavelength can't do in the photoelectric effect?

Rebecca Chu 1C

Planck's constant is used to calculate the energy of one photon in a wavelength. (Dr. Lavelle showed us an example where we use Planck's constant in Friday's lecture.)

Rebecca Chu 1C

The empirical formula expresses the atoms in a molecule/compound in terms of ratios. The molecular formula shows the actual number of atoms in a molecule/compound. Some molecules can have the same empirical formula (e.g. glucose and acetic acid both have the empirical formula of CH_{2}O but glucose ...

Rebecca Chu 1C

What exactly is the difference between the wave model and particle model?

Rebecca Chu 1C

Does anyone know why only one photon affects only one electron? Why can't multiple photons affects one electron?

Rebecca Chu 1C

"Epsom salts consist of magnesium sulfate heptahydrate. Write its formula. (a) How many atoms of oxygen are in 5.15 g of Epsom salts?" I referred to the solutions manual while solving for the atoms of O. It used 11 mol O atoms in the dimensional analysis, but I'm confused why it isn't just...

CHEMISTRY COMMUNITY

Search found 27 matches

Charge on ligands? [ENDORSED]

Test 3 Q7

4 ligands shape?

Re: Phosphate Lewis structure?

Phosphate Lewis structure?

Partial charge or full charge

Re: Double bond

Central atom and octet rule?

Re: Meaning of a dipole

Formal Charge Shortcut

Covalent Character?

Lewis acid vs. base

Re: Energy difference between 4s and 3d

Re: test 1

Re: test 1, question 7

Parallel vs Paired Electrons

Nodes

Re: Radius

Re: Interference [ENDORSED]

Re: Week 3 discussion, question 6 [ENDORSED]

Re: hw 1.23 [ENDORSED]

Photoelectric Effect and its light intensity [ENDORSED]

Re: How do I use Planck's constant? [ENDORSED]

Re: Quiz 1

Difference between wave model and particle model? [ENDORSED]

Photoelectric Effect

Homework Question E9a