Search found 30 matches

by Julia Lung 1I
Sat Mar 16, 2019 1:11 pm
Forum: Balancing Redox Reactions
Topic: How to tell if its in acidic or basic
Replies: 6
Views: 94

Re: How to tell if its in acidic or basic

It's usually acidic unless otherwise stated
by Julia Lung 1I
Tue Mar 12, 2019 10:33 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7420
Views: 980089

Re: Post All Chemistry Jokes Here

I would tell another chemistry joke
...but all the good ones Argon.
by Julia Lung 1I
Tue Mar 12, 2019 10:33 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7420
Views: 980089

Re: Post All Chemistry Jokes Here

Why does hamburger have less energy than steak?

It's the ground state.
by Julia Lung 1I
Tue Mar 12, 2019 10:29 pm
Forum: General Rate Laws
Topic: Unique rate law
Replies: 1
Views: 48

Unique rate law

In what situation would we use the rate of formation or the unique rate law? How will we be able to tell?
by Julia Lung 1I
Tue Mar 12, 2019 10:26 pm
Forum: Administrative Questions and Class Announcements
Topic: Sig Figs
Replies: 9
Views: 287

Sig Figs

I heard from my TA that sig figs will be graded. Has anyone heard something similar or different?
by Julia Lung 1I
Tue Mar 12, 2019 10:23 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7420
Views: 980089

Re: Post All Chemistry Jokes Here

What's the difference between chemistry jokes and physics jokes?

Chemistry jokes can be funny periodically, but physics jokes have more potential.
by Julia Lung 1I
Tue Mar 12, 2019 9:34 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Test #2 4b
Replies: 2
Views: 53

Test #2 4b

Why wouldn't you put H2O(l) into the cell diagram the it is given on the cathode side?
by Julia Lung 1I
Tue Mar 12, 2019 9:25 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Formulas
Replies: 6
Views: 97

Re: Formulas

There are three equations that are given connecting Ecell, K and DeltaG if you're given one you can find the others.
by Julia Lung 1I
Tue Mar 12, 2019 9:11 pm
Forum: General Rate Laws
Topic: Equations
Replies: 2
Views: 45

Re: Equations

The reason why you haven't seen it on the constants and equations sheet is because we didn't need it for the two test or the midterm, but it will be on the final. The final constants and equations sheet should be on the Chem 14B website.
by Julia Lung 1I
Wed Mar 06, 2019 9:51 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7420
Views: 980089

Re: Post All Chemistry Jokes Here

What kind of fish is made out of 2 sodium atoms?


2Na
by Julia Lung 1I
Wed Mar 06, 2019 9:45 pm
Forum: General Rate Laws
Topic: Deriving Rate Laws
Replies: 3
Views: 64

Deriving Rate Laws

Will we have to be able to derive the rate laws for the final or just understand what is going on and how to use it?
by Julia Lung 1I
Wed Mar 06, 2019 9:41 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: Instantaneous vs Average
Replies: 11
Views: 135

Re: Instantaneous vs Average

average rate is when you take the change over time while instantaneous is usually when time is approaching zero and you take the derivative
by Julia Lung 1I
Wed Mar 06, 2019 9:39 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Test #2
Replies: 10
Views: 179

Re: Test #2

Tests are given back in your discussion section
by Julia Lung 1I
Wed Feb 27, 2019 7:26 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Galvanic Cell Diagram [ENDORSED]
Replies: 3
Views: 92

Galvanic Cell Diagram [ENDORSED]

In a galvanic cell diagram, I know we put a line between the solids and the aqueous solution and a comma between different aqueous molecules in the same beaker, but would we use a comma or a line to separate gas and aqueous in the same beaker?
by Julia Lung 1I
Sun Feb 24, 2019 3:23 pm
Forum: Balancing Redox Reactions
Topic: 6th edition 14.5a
Replies: 1
Views: 32

6th edition 14.5a

The problem asks you to balance the reaction using redox half rxns: O3 + Br- ----> O2 + BrO3-
For this problem O3 is oxidized = 0 to O2 which is -2, I thought O2 is suppose to equal 0 can anyone explain why and in what situations O2 would equal 0 or -2?
by Julia Lung 1I
Sun Feb 24, 2019 1:05 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Test 2
Replies: 9
Views: 167

Test 2

What part of Gibbs Free Energy should we know for the second test?
by Julia Lung 1I
Thu Feb 14, 2019 11:59 am
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Topic: 6th edition 9.11
Replies: 1
Views: 194

6th edition 9.11

Calculate the change in entropy when the pressure of 1.50 mol Ne(g) is decreased isothermally from 15.0 atm to 0.500 atm. Assume ideal behavior. I got the right answer for this problem using ΔS=nRln(P1/P2) = ΔS=(1mol)(8.314 J/k*mol)ln(15.0atm/0.500atm) = 42.2J/K but I'm confused how the units cancel...
by Julia Lung 1I
Sun Feb 10, 2019 2:20 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: 8.73 Help (Bond Enthalpy)
Replies: 2
Views: 68

Re: 8.73 Help (Bond Enthalpy)

The solution only calculated the C-C bonds so there would be 3 mol of the CC triple bond broken and 6 mol of the C-C formed from the benzene ring.
by Julia Lung 1I
Sun Feb 10, 2019 2:16 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Hess's Law
Replies: 3
Views: 84

Re: Hess's Law

Usually the problem gives you values or tells you what method to use to solve for the enthalpy
by Julia Lung 1I
Mon Feb 04, 2019 2:35 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Standard formation deltaH
Replies: 2
Views: 41

Re: Standard formation deltaH

Standard Enthalpy of Formation (deltaH) is the most stable form of a molecule. You would use: ΔH(of formation) = Sum of ΔH(of formation of products) - ΔH(of formation of reactants). This is the 3rd method to find enthalpy changes from last weeks lecture.
by Julia Lung 1I
Sat Feb 02, 2019 1:42 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Week 5 Homework
Replies: 4
Views: 72

Week 5 Homework

What chapter is this week's homework suppose to be on? Do we continue with chapter 8?
by Julia Lung 1I
Sat Feb 02, 2019 1:38 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Test Question
Replies: 4
Views: 97

Re: Test Question

Usually the problems specify whether to find the concentration or partial pressure, you can use Kc to also find the K of gases but I think they want us to use Kp for gases
by Julia Lung 1I
Sat Feb 02, 2019 1:35 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: U:Internal Energy
Replies: 4
Views: 72

Re: U:Internal Energy

They can both be used to find delta U depending on what's given in the problem. We also went over that when there is no volume change (in most of biology) then delta U = delta H.
by Julia Lung 1I
Wed Jan 30, 2019 9:29 am
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Homework #3
Replies: 2
Views: 43

Homework #3

Do we only do problems on thermochemistry chapter 8?
by Julia Lung 1I
Tue Jan 29, 2019 11:28 am
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Sig Figs with Enthalpy
Replies: 4
Views: 77

Re: Sig Figs with Enthalpy

Yes, use sig figs at the end when you add the enthalpies. I don't think they're that strict on it though.
by Julia Lung 1I
Thu Jan 24, 2019 11:31 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: converting between kp and kc
Replies: 4
Views: 78

Re: converting between kp and kc

There's also an equation that goes from Kc to Kp
Kp=Kc(RT)^delta(n) or Kp=(T/12.03)^delta(n)*Kc
by Julia Lung 1I
Thu Jan 24, 2019 10:42 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Ka and Kb values
Replies: 1
Views: 50

Ka and Kb values

I'm confused on how to select the correct Ka and Kb value from the table given in the textbook when they are not exactly what's in the problem. For example, in 12.71 to calculate the pH of 0.63M of NaCH3CO2(aq) would I just use the Ka value for acetic acid CH3COOH (1.8x10^-5)?
by Julia Lung 1I
Wed Jan 16, 2019 9:39 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: ICE
Replies: 5
Views: 100

Re: ICE

X represents the change in concentration, it can either be positive or negative whether it is increasing or decreasing.
by Julia Lung 1I
Sun Jan 13, 2019 9:07 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Equilibria Changes
Replies: 3
Views: 49

Re: Equilibria Changes

You would use the initial concentration mostly for the ICE table
by Julia Lung 1I
Sat Jan 12, 2019 1:52 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Homework 11.79 6th edition
Replies: 2
Views: 55

Homework 11.79 6th edition

What is the significance of using bar for units and what would be the easiest approach for problems like 11.79 6th edition? 11.79 A reactor for the production of ammonia by the Haber process is found to be at equilibrium with PN2  3.11 bar, PH2  1.64 bar, and PNH3  23.72 bar. If the partial press...

Go to advanced search