Search found 15 matches

by Angela He 3B
Tue Mar 08, 2016 12:25 am
Forum: *ChemDraw
Topic: Cyclohexanes
Replies: 1
Views: 739

Re: Cyclohexanes

Interconversion refers to the change between conformations (look at the diagram at the bottom of page 113). The rapid interconversion between the two chair cyclohexane conformations make the hydrogens equivalent, so the chair conformations are equal in energy.
by Angela He 3B
Fri Feb 26, 2016 12:04 am
Forum: *Constitutional and Geometric Isomers (cis, Z and trans, E)
Topic: self-test 1.4A
Replies: 1
Views: 385

self-test 1.4A

This question asks to write the IUPAC names (and when possible common names) for all the constitutional isomers of C6H14, and the answers are n-hexane, 2-methylpentane (isohexane), 3-methylpentane, 2,2,-dimethylbutane (neohexane), and 2,3-dimethylbutane. I understand most of the answers, but isn't 3...
by Angela He 3B
Fri Feb 19, 2016 12:44 am
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: "reaction profile" & k (quiz 2 preparation)
Replies: 1
Views: 373

"reaction profile" & k (quiz 2 preparation)

What does the energy diagram say about k?
by Angela He 3B
Fri Feb 12, 2016 9:26 pm
Forum: General Rate Laws
Topic: concentration of first-order integrated rate law
Replies: 1
Views: 507

concentration of first-order integrated rate law

This is a textbook example and it seems super simple but i don't know what happened in the Self-test "The rate law for the decomposition of 2N2O (g) -> 2N2 (g) + O2 (g) is Rate of decomposition of N2O = k[N2O]. Calculate the concentration of N2O remaining after the reaction has continued at 780...
by Angela He 3B
Sat Feb 06, 2016 9:09 pm
Forum: Balancing Redox Reactions
Topic: electrochemistry ch question 13.d
Replies: 2
Views: 457

electrochemistry ch question 13.d

"Write the half-reactions, the balanced equation for the cell reaction, and the cell diagram for each of the following skeletal equations: d) Au + (aq) -> Au(s) + Au 3+ (aq)" I'm not sure how to derive the half reactions. The answers are Au + (aq) + e - -> Au(s) and "Au(s) -> Au 3+ (a...
by Angela He 3B
Tue Feb 02, 2016 11:51 pm
Forum: Phase Changes & Related Calculations
Topic: Monatomic Ideal Gas
Replies: 2
Views: 642

Re: Monatomic Ideal Gas

Cv= (3/2)R is used for the heat capacity in ideal gas reversible expansion problems at constant volume. Cp= (5/2)R is used for the same purpose but at constant pressure
by Angela He 3B
Sat Jan 30, 2016 12:01 am
Forum: Balancing Redox Reactions
Topic: Electrochem basics
Replies: 1
Views: 293

Re: Electrochem basics

If you look at a diagram of a battery system (you can just look one up online "electrochemistry battery illustration with labels"), you can see what the anode and cathode is. The anode is the electrode where oxidation is taking place, so it should be losing the electrons, and the cathode i...
by Angela He 3B
Thu Jan 21, 2016 8:32 am
Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
Topic: Increase in Disorder
Replies: 2
Views: 613

Re: Increase in Disorder

Entropy is essentially the degree of disorder in a system. If entropy is positive, it means the reaction is spontaneous and increasing in disorder.
by Angela He 3B
Sat Jan 16, 2016 12:15 am
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: Spontaneous Change and Entropy
Replies: 1
Views: 266

Re: Spontaneous Change and Entropy

The entropy for the hot block of metal cooling down to the temperature of the surroundings would have a positive value. The reverse reaction would have the same value, but it would be a negative value, meaning that there's a decrease in entropy and the system is becoming less disordered.
by Angela He 3B
Mon Nov 30, 2015 10:56 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: VIdeo: Chemical Equilibrium
Replies: 1
Views: 339

VIdeo: Chemical Equilibrium

Sorry about the delay in posting, I had some issues with file format. My partner Jane Park has already posted a video.
by Angela He 3B
Mon Nov 30, 2015 10:29 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Video: Equilibrium concepts and examples
Replies: 2
Views: 394

Re: Video: Equilibrium concepts and examples

Chem Equilibrium.mp4 [ 171.95 MiB | Viewed 359 times ]



do I also need to attach it myself to receive credit even though Jane mentioned my name?
by Angela He 3B
Mon Nov 16, 2015 10:39 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: ICE BOX
Replies: 1
Views: 277

Re: ICE BOX

The coefficients of the x's in the change part of the ICE box is determined by the number of moles, and the +/- is determined by the direction of the reaction.

I hope this helps!
by Angela He 3B
Wed Oct 28, 2015 8:05 pm
Forum: Hybridization
Topic: S-character of a hybrid orbital
Replies: 2
Views: 3421

Re: S-character of a hybrid orbital

s character basically refers to the s in the hybrid orbital, so for example sp3 would be 25% s character and 75% p character. The bond angle would increase when the s character increases because there is a decrease in the p character, which would mean less electron densities around the central atom....
by Angela He 3B
Sat Oct 17, 2015 9:34 pm
Forum: Properties of Electrons
Topic: Valence electrons
Replies: 1
Views: 428

Re: Valence electrons

Transition metals' valence electrons would be removed first from the s-orbitals before the d-orbitals. So for example, scandium would be [Ar]3d14s2 not [Ar]4s23d1 because 3d orbitals are lower in energy than 4s, so the valence electrons would be the 3d1 and 4s2. The explanation for it is on page 59 ...
by Angela He 3B
Fri Oct 02, 2015 3:03 pm
Forum: *Shrodinger Equation
Topic: Orbitals?
Replies: 1
Views: 346

Re: Orbitals?

Orbitals are areas where the electrons are around the nucleus. They're denoted by s, p, d, f, and g. Wave functions are used to describe an electron in an atom and describe the probability of finding electrons at certain energy levels, and since orbitals are areas where the electrons are most likely...

Go to advanced search