## Search found 32 matches

Sun Dec 09, 2018 11:47 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: Calculating pH of salt solution with acidic cation
Replies: 5
Views: 475

### Re: Calculating pH of salt solution with acidic cation

Thank you!!
Sun Dec 09, 2018 11:45 pm
Forum: Air Pollution & Acid Rain
Topic: Acid Rain
Replies: 15
Views: 1505

### Re: Acid Rain

SO2 as it results from fossil fuel combustion
Sun Dec 09, 2018 11:42 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Forces
Replies: 1
Views: 263

### Re: Forces

I could be wrong but from what I've read, the state of a substance more so depends on the temperature and pressure acting upon the already existing IMF's, such as water having hydrogen bonds but going between gas, liquid, and solid depending on environmental conditions
Sun Dec 09, 2018 11:39 pm
Forum: Polyprotic Acids & Bases
Topic: Polyprotic Question!
Replies: 12
Views: 1069

### Re: Polyprotic Question!

If an acid is polyprotic is it stronger?
Sat Dec 08, 2018 2:40 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: Calculating pH of salt solution with acidic cation
Replies: 5
Views: 475

### Calculating pH of salt solution with acidic cation

Hey friends,
I read that we won't need to know the Ka and Kb constants until 14B, and these are necessary for Examples 12.10-11 in the 6th edition, so will we not be responsible for knowing how to do these kinds of calculations on the final?
Thanks
Fri Dec 07, 2018 6:21 pm
Forum: Bronsted Acids & Bases
Topic: Problem J.7 - 7th Ed.
Replies: 4
Views: 262

### Re: Problem J.7 - 7th Ed.

In order to do part b on this problem we need to know the formula for zinc nitrite but I keep getting conflicting answers on the internet, does anyone know the right formula?
Sun Nov 25, 2018 3:58 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: Distortion and London Dispersion Forces
Replies: 2
Views: 138

### Re: Distortion and London Dispersion Forces

London forces rely on random moments in which electrons are clustered at one particular area of the atom, and this happens more often with higher polarizability, or ability to be distorted. With a higher atomic radius, the nucleus has less control over the surrounding electrons, so the electrons are...
Sun Nov 25, 2018 3:51 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Intermolecular energy
Replies: 3
Views: 418

### Re: Intermolecular energy

Alpha stands for the polarizability of the molecules, alpha 1 being the polarizability of the first molecule multiplied by alpha 2, the polarizability of the second molecule.
Sun Nov 25, 2018 3:46 pm
Forum: Dipole Moments
Topic: distinguishing dipole moments
Replies: 1
Views: 137

### Re: distinguishing dipole moments

Vectors having to do with dipoles denote the direction of charge going from positive to negative or negative to positive. In the molecule H20, attached is a picture of the vector of the bent molecule in which the vector goes from the positive upward bent hydrogen atoms down to the downward negative ...
Sun Nov 18, 2018 9:47 pm
Forum: Administrative Questions and Class Announcements
Topic: Homework Week 8 [ENDORSED]
Replies: 7
Views: 1751

### Re: Homework Week 8[ENDORSED]

Even though we still have discussion for Mon-Wed is our homework still due the next week as well? Sorry, just to be sure.
Sun Nov 18, 2018 9:42 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Resonance Structures and bond angles
Replies: 4
Views: 830

### Re: Resonance Structures and bond angles

Resonance structures would not affect bond angles as the shape is based upon atom structure, which does not change in resonance. As for electrons and lone pairs, a molecule with multiple resonance structures would actually have a hybrid of all possible electron configurations so different resonance ...
Tue Nov 13, 2018 12:25 pm
Forum: Administrative Questions and Class Announcements
Topic: Homework Week 8 [ENDORSED]
Replies: 7
Views: 1751

### Re: Homework Week 8[ENDORSED]

Is this for all discussions or just for Thursday and Friday discussions?
Sun Nov 11, 2018 3:35 pm
Forum: Ionic & Covalent Bonds
Topic: Determining ionic character vs covalent
Replies: 3
Views: 171

### Re: Determining ionic character vs covalent

On a related note, do you know if we will be responsible for knowing exact electronegativity values or should we just know the general trend?
Sun Nov 11, 2018 3:27 pm
Forum: Hybridization
Topic: How to Determine
Replies: 12
Views: 561

### Re: How to Determine

Are you referring to hybridization of atomic orbitals?
Sun Nov 11, 2018 3:26 pm
Forum: Hybridization
Replies: 4
Views: 203

I believe Dr. Lavelle looks at the class average and sets a grading scheme based upon how well everyone did. Based off of the grading scheme on Bruin Walk, a majority of people received A's.
Sun Nov 04, 2018 8:47 pm
Forum: Ionic & Covalent Bonds
Topic: Chem Midterm
Replies: 13
Views: 537

### Re: Chem Midterm

Nick Bazett 1F wrote:Do we take the midterm in pen or pencil?

I believe it needs to be in pen just like previous tests.
Sun Nov 04, 2018 8:44 pm
Forum: Octet Exceptions
Topic: Copper
Replies: 10
Views: 434

### Re: Copper

It helps me to think about it being more beneficial to have a full shell of 10 electrons rather than a full shell of 2 electrons. Remember this is also the case for Cr, in which a half shell of 3d5 with all electrons of the same spin is more stable than having a full 4s2 and 3d4.
Mon Oct 29, 2018 9:54 pm
Forum: Trends in The Periodic Table
Topic: Ionization energies
Replies: 9
Views: 1030

### Re: Ionization energies

Thank you!
Christine Chow 4G wrote:I believe oxygen has a lower ionization energy due to the fact that its 8th electron becomes paired (the up and down spin) versus filling a new orbital. There would be more electron repulsion in this pair versus the other 3p electrons that are in their own orbital (x,y,z)
Mon Oct 29, 2018 9:19 pm
Forum: Trends in The Periodic Table
Topic: Ionization energies
Replies: 9
Views: 1030

### Re: Ionization energies

Oxygen is to the right of Nitrogen, why does it have a lower ionization energy than Nitrogen if ionization energy increases to the right?
Sun Oct 28, 2018 7:14 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: px,py,pz???
Replies: 6
Views: 795

### Re: px,py,pz???

px, py, and pz simply refers to the location of the orbitals based on the Cartesian axes. I'm guessing in an exam, you would just use the 2p6 notation unless the orbital locations are specfically asked for in the question.
Tue Oct 23, 2018 7:54 pm
Forum: Photoelectric Effect
Topic: Example 1.5 6th edition
Replies: 2
Views: 202

### Example 1.5 6th edition

Example 1.5 includes converting from eV to to J, is this a kind of conversion we should know for Test 2?
Tue Oct 23, 2018 6:58 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Building- Up Principle
Replies: 5
Views: 215

### Re: Building- Up Principle

Do we need to know these exceptions for the test tomorrow?
Mon Oct 22, 2018 4:08 pm
Forum: Quantum Numbers and The H-Atom
Topic: HW 2.19
Replies: 3
Views: 147

### Re: HW 2.19

I have a question about 2.19 regarding part d. I understand that from n=4 equates to n-1=3 and l=3. Therefore, there are s, p, d, and f suborbitals but I don't understand why the answer says the suborbitals are 4s, 4p, 4d, and 4f. What are the 4's for?
Sun Oct 21, 2018 5:43 pm
Forum: Photoelectric Effect
Topic: Work Function
Replies: 16
Views: 364

### Re: Work Function

In metals, free electrons may float about the metal but do not have enough energy to escape from the surface. When additional energy is added in the form of a photon that reaches the threshold energy, these free electrons can escape from the surface of the metal and be emitted
Sun Oct 21, 2018 4:52 pm
Forum: Properties of Electrons
Topic: Electrons - Wave Properties
Replies: 4
Views: 173

### Re: Electrons - Wave Properties

You can find the wavelength of an electron moving at a certain velocity by using the DeBroglie equation. Wavelength is equal to Planck's constant h divided by momentum p, which is equivalent to mass m multiplied by velocity v. In this case, you would use the given mass of an electron and the velocit...
Sun Oct 21, 2018 4:40 pm
Forum: Properties of Light
Topic: Test 2
Replies: 7
Views: 367

### Re: Test 2

The tests will always be free response and should be about the same length as Test 1.
Mon Oct 15, 2018 3:44 pm
Forum: DeBroglie Equation
Topic: HW 1.41
Replies: 6
Views: 125

### HW 1.41

This might be a dumb question but for Chapter 1 Number 41 when we are asked to calculate the velocity of a neuron of wavelength 100. pm, why do we have to use the DeBroglie equation instead of just c=λv?
Thu Oct 11, 2018 6:17 pm
Forum: Properties of Light
Topic: Threshold Energy
Replies: 11
Views: 348

### Re: Threshold Energy

The threshold energy is a minimum amount of energy that a photon (think a packet of energy) has to reach to eject an electron from an atom of a certain metal. Threshold energy is determined by the type of metal, and different metals have different threshold energies for its atoms/electrons.
Thu Oct 11, 2018 6:06 pm
Forum: Properties of Electrons
Topic: Mass of Electrons and Photons
Replies: 2
Views: 137

### Re: Mass of Electrons and Photons

Traditionally and from what is required of us in this course, photons are considered massless.
Thu Oct 11, 2018 3:43 pm
Forum: SI Units, Unit Conversions
Topic: Atoms and Molecules
Replies: 5
Views: 185

### Re: Atoms and Molecules

Like said above, pay attention to the what the problem is asking for. A question can ask for the atoms of H in the molecule H2O for example, in which you would have to use Avogadro's number and then multiply by two to account for the two hydrogen atoms for every molecule of H2O.
Mon Oct 08, 2018 3:49 pm
Forum: Administrative Questions and Class Announcements
Replies: 135
Views: 31735