## Search found 20 matches

Sun Dec 09, 2018 1:44 am
Forum: Administrative Questions and Class Announcements
Topic: FINAL PRACTICE - Lyndon's Churro Review Session [ENDORSED]
Replies: 118
Views: 13702

### Re: FINAL PRACTICE - Lyndon's Churro Review Session[ENDORSED]

I think I understand the basis of how to do number 34, but I keep getting a pH of 2.10. Did anyone else make the error same/know what my error is? I'm getting that same answer :( The 1st step is to write out the acid and base equation, [HCl] + [H2O] =>[H3O^+] + [OH^-] and [CaO] + [H2O] => [Ca^+] + ...
Sun Dec 09, 2018 1:15 am
Forum: Administrative Questions and Class Announcements
Topic: FINAL PRACTICE - Lyndon's Churro Review Session [ENDORSED]
Replies: 118
Views: 13702

### Re: FINAL PRACTICE - Lyndon's Churro Review Session[ENDORSED]

for 33a, how do we set up the equation with 1.5mol/L and 0.1155mol/210ml to find the mL require for the 1.5M solution?
Mon Nov 26, 2018 12:00 am
Forum: Bond Lengths & Energies
Topic: How to Measure Bond Lengths
Replies: 4
Views: 251

### Re: How to Measure Bond Lengths

I believe we only need to know the trend, if we need it on the exam we will be given the specific one.
Sun Nov 25, 2018 11:57 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: MO theory
Replies: 2
Views: 190

### Re: MO theory

As for in what order to fill the orbitals, draw out an underscore for space where each pair of e- can fill and only put 1 e- in until you run out of empty ones before you put another e- in the same orbital.
Sun Nov 25, 2018 11:54 pm
Forum: Hybridization
Topic: Question 4.45 (Sixth Edition)
Replies: 1
Views: 135

### Re: Question 4.45 (Sixth Edition)

hybrid orbitals on something like C is when ground state C, which has 2 e- in 2s orbital and 2 e- in 2p orbital, combine to form 4e- in a single 2sp orbital, so each e- is available to bond.
Sun Nov 11, 2018 11:55 pm
Forum: General Science Questions
Topic: Homework Problem help #2.39
Replies: 1
Views: 182

### Re: Homework Problem help #2.39

The ground state of an element is in order, an electron in the excited state can be in any other n level (as long as it got excited enough). So if the electron configuration jumps out of order, the atom must have excited electrons.
Sun Nov 11, 2018 11:52 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: How do you utilize the VSEPR model?
Replies: 4
Views: 155

### Re: How do you utilize the VSEPR model?

Basically you count the numbers of bond pairs and lone pairs a molecule has, then look at the chart to find the corresponding molecular shape.
For example a molecule with 2 bonds and 0 lone pairs is corresponded to the "linear" shape.
Sun Nov 04, 2018 11:42 pm
Forum: Lewis Structures
Topic: Acids and Bases
Replies: 3
Views: 173

### Re: Acids and Bases

Lewis acids accept electrons, and Lewis bases donate electrons. If the molecule has an H+ ion in its structure, then it can take some e- and therefore it is a Lewis acid.
Sun Nov 04, 2018 11:39 pm
Forum: Dipole Moments
Topic: Polar and Nonpolar
Replies: 7
Views: 348

### Re: Polar and Nonpolar

It comes down to if the molecule has charged regions (e- spending more time near one atom instead of both), and if charge regions are positioned to balance the charge (example: two (-) charged atom on either side of a (+) charged atom).
Sun Nov 04, 2018 11:35 pm
Forum: Lewis Structures
Topic: Lewis Structures
Replies: 3
Views: 141

### Re: Lewis Structures

if you set up the Lewis structure correctly, and know your electronegativity, then you can figure which molecule keeps the shared e- longer (more negative). Then look at the angles and placement of those charged regions, if the charge molecules are skewed to one side, or not balanced with another ch...
Fri Oct 26, 2018 10:38 am
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Electron Configuration Help
Replies: 3
Views: 195

### Re: Electron Configuration Help

For electron configurations, literally, write down the number of electrons in each orbital of the atom. For example, Hydrogen has 1 electron and it's in 1s orbital, so the EC for that is: 1s^1 Lithium has 3 electrons, 2 in 1s orbital, 1 in 2s orbital, so EC for Li is: 1s^2 2s^1 Carbon has 6 electron...
Fri Oct 26, 2018 10:33 am
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Exceptions to Trends
Replies: 3
Views: 175

### Re: Exceptions to Trends

The profession also mentions that what he said is a theory of why the phenomenon occurs, so maybe the science world doesn't fully understand it yet.
Fri Oct 26, 2018 10:25 am
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Homework 2.43e
Replies: 3
Views: 227

### Re: Homework 2.43e

I think this phenomenon only applies to the first row of d-orbitals/d-states, so like Cr and Cu, but not any other d-state (4d, 5d...etc)
Sun Oct 21, 2018 11:33 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Replies: 3
Views: 222

### Re: About Uncertainty in position

I believe the diameter of the atom is twice of "delta x," it looks like the question wants you to put 1/2 of that diameter into the uncertainty equation in delta x and solve of velocity.
Mon Oct 15, 2018 10:35 am
Forum: Einstein Equation
Topic: Kinetic energy and e = hv
Replies: 3
Views: 200

### Re: Kinetic energy and e = hv

I would think if Ek is 0, then the electron is not ejected. For the experiment, they had a slightly positive surface that will attract the electron with a small amount of Ek.
Mon Oct 15, 2018 10:31 am
Forum: Properties of Light
Topic: Threshold energy
Replies: 2
Views: 144

### Re: Threshold energy

In a photoelectric effect, a radiation (Ep) applied at a metallic surface , and if the radiation is greater the the threshold energy (work function) of the metal, an electron will be ejected (Ek).

The threshold energy/work function is how much energy is need to eject the electron from the metal.
Tue Oct 09, 2018 5:21 pm
Forum: Photoelectric Effect
Replies: 2
Views: 148

For Ch1 #3, the question asks what happens when the frequency of electromagnetic radiation decreases. I think the equation is speed of light = frequency x wavelength (a)The speed of the radiation decreases. I thought the speed is always the same? (b)The wavelength of the radiation decreases. the wav...
Sun May 06, 2018 11:42 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: electron config in the "d" sublevel
Replies: 5
Views: 391

### electron config in the "d" sublevel

For the electron configuration, when we get into an element in the "d" sublevel, why do we do something like "3d10 4s1" instead of "3d9 4s2?"
Sun Apr 15, 2018 10:16 pm
Forum: General Science Questions
Topic: Energy (photon) - Energy (remove e-???) [ENDORSED]
Replies: 4
Views: 573

### Re: Energy (photon) - Energy (remove e-???)[ENDORSED]

So the energy to remove e- is related to the frequency of the light, what is the "Energy (Photo)" ? I thought that was the energy of the light
Sat Apr 14, 2018 9:44 pm
Forum: General Science Questions
Topic: Energy (photon) - Energy (remove e-???) [ENDORSED]
Replies: 4
Views: 573

### Energy (photon) - Energy (remove e-???)[ENDORSED]

During last Friday's (Week 2) lecture, the example for the equation E(photon) - E (remove e-) ＝ kinetic E, and the picture that showed light hitting a piece pf metal and bouncing off, how is the piece pf metal actively putting energy to remove the e-?? What is going on here??