Search found 53 matches
- Sun Mar 15, 2020 1:57 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Saying Thank You to Dr. Lavelle
- Replies: 490
- Views: 513040
Re: Saying Thank You to Dr. Lavelle
He was dope! A very funny dude and he made class fun :^)
- Sun Mar 15, 2020 1:56 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Chem Final Typo
- Replies: 8
- Views: 800
Re: Chem Final Typo
I was wondering this too!! I didn’t know if I should email him or not :/
- Sun Mar 15, 2020 1:55 pm
- Forum: Van't Hoff Equation
- Topic: Chemistry analysis
- Replies: 5
- Views: 443
Re: Chemistry analysis
I was confused about this too, but I don’t think there’s any difference between chemistry van’t hoff and van’t hoff.
- Sun Mar 15, 2020 1:51 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2984003
Re: Post All Chemistry Jokes Here
Atoms are hard to trust. I heard they make up everything...
- Sun Mar 15, 2020 1:49 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2984003
Re: Post All Chemistry Jokes Here
Someone threw sodium chloride at me. I’m still salty.
- Sun Mar 15, 2020 1:48 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2984003
Re: Post All Chemistry Jokes Here
I would tell you a joke about chemistry, but they Argon.
- Sun Mar 15, 2020 1:46 pm
- Forum: Student Social/Study Group
- Topic: Final Jitters
- Replies: 457
- Views: 333852
Re: Final Jitters
I hope all of this advice helped! :)
- Sun Mar 15, 2020 1:45 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Athena
- Replies: 34
- Views: 3035
Re: Athena
Thanks for being such a cool professor! I wish you the best!
- Sun Mar 08, 2020 8:32 pm
- Forum: Student Social/Study Group
- Topic: Post All Chemistry Jokes Here
- Replies: 9651
- Views: 2984003
Re: Post All Chemistry Jokes Here
If Silver Surfer and Iron Man teamed up, they’d be alloys.
- Sun Mar 08, 2020 8:26 pm
- Forum: Balancing Redox Reactions
- Topic: e- amount
- Replies: 9
- Views: 595
e- amount
If the number of e- don’t match on both sides of the reaction, then did I balance the redox reaction incorrectly? Do they have to be the same for the reactant and product/cancel out?
- Sun Mar 08, 2020 8:23 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Vertical lines vs commas
- Replies: 7
- Views: 418
Re: Vertical lines vs commas
Use vertical lines between different phases (i.e. s|g|l|aq) and double vertical lines between anode and cathode (anode||cathode). Use commas between molecules of the same phase ( i.e Pt(s), C(s) )
- Sun Mar 08, 2020 8:21 pm
- Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
- Topic: Figuring out n
- Replies: 15
- Views: 925
Re: Figuring out n
In this equation, n is equal to the number of electrons being transferred, so you would first have to balance the half reactions.
- Sun Mar 08, 2020 8:16 pm
- Forum: Van't Hoff Equation
- Topic: Van't Hoff Equation
- Replies: 6
- Views: 541
Re: Van't Hoff Equation
There are many ways to manipulate the equation, as you can manipulate the variables solve for dH, K2, K1, T2, and T1. The main use for the equation is to relate the change in K to the change in temperature.
- Sun Mar 08, 2020 8:10 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: calculating Q
- Replies: 12
- Views: 726
calculating Q
When finding Q in the nernst equation, is it always [cathode]/[anode] or is it [anode]/[cathode] ?
- Sun Mar 01, 2020 5:09 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Salt Bridge
- Replies: 3
- Views: 229
Salt Bridge
If there isn't a salt bridge, then how are the charges maintained/balanced?
- Sun Mar 01, 2020 4:58 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Galvanic vs Electrolytic Cell
- Replies: 1
- Views: 153
Galvanic vs Electrolytic Cell
I know the difference between the two cells is because of the charge of the anode/cathode, but how do you know whether the anode/cathode is positive or negative?
- Sun Mar 01, 2020 4:55 pm
- Forum: Balancing Redox Reactions
- Topic: Anode and Cathode
- Replies: 9
- Views: 523
Anode and Cathode
How can you tell which solution is the anode and which solution is the cathode? How do you know which way the electrons are flowing?
- Sun Mar 01, 2020 4:50 pm
- Forum: Balancing Redox Reactions
- Topic: H+ or H2O
- Replies: 4
- Views: 288
H+ or H2O
How do you know when you need H+ or H2O? How do you know you need to balance O or H?
- Sun Feb 23, 2020 11:24 pm
- Forum: Van't Hoff Equation
- Topic: Van’t Hoff Equation
- Replies: 11
- Views: 901
Van’t Hoff Equation
What does the equation measure? How does it relate to gibbs free energy?
- Sun Feb 23, 2020 11:15 pm
- Forum: Balancing Redox Reactions
- Topic: Test 2 Topics
- Replies: 7
- Views: 479
Test 2 Topics
Will test 2 include all topics learned during week 8 also?
- Sun Feb 23, 2020 11:12 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Sapling Learning
- Replies: 6
- Views: 549
Re: Sapling Learning
They’re helpful if you want extra practice problems, but some of it is pretty simple. It’s helpful to learn the basics of a topic.
- Sun Feb 23, 2020 11:07 pm
- Forum: Balancing Redox Reactions
- Topic: Reduced/Oxidized
- Replies: 5
- Views: 343
Reduced/Oxidized
If you’re not given the charge, how would you know which elements/molecules are reduced or oxidized?
- Sun Feb 23, 2020 11:01 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: applying gibbs free energy
- Replies: 5
- Views: 405
Re: applying gibbs free energy
Gibbs free energy tells us about the spontaneity of a reaction. If it is less than 0, then the process is exergonic and will proceed spontaneously in the forward direction. If it is greater than 0, then the process is endergonic and will proceed spontaneously in the reverse direction. If it is equal...
- Sun Feb 16, 2020 8:21 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: S = 0
- Replies: 21
- Views: 1127
Re: S = 0
Entropy is 0 in an isothermal reversible system.
- Sun Feb 16, 2020 8:14 pm
- Forum: Gibbs Free Energy Concepts and Calculations
- Topic: Spontaneous
- Replies: 13
- Views: 739
Re: Spontaneous
A reaction is spontaneous when delta G is less than 0.
- Sun Feb 16, 2020 8:11 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Delta s = 0
- Replies: 8
- Views: 658
Re: Delta s = 0
delta S is equal to 0 in an isothermal reversible system.
- Sun Feb 16, 2020 8:07 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Delta U
- Replies: 8
- Views: 550
Re: Delta U
Delta U is the change in internal energy. Internal energy is the energy contained within a system.
- Sun Feb 09, 2020 7:11 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Reversible vs Irreversible
- Replies: 7
- Views: 431
Re: Reversible vs Irreversible
When a system is reversible, dStotal = dSsystem + dSsurroundings is equal to 0.
- Sun Feb 09, 2020 6:58 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: state function mnemonic device
- Replies: 3
- Views: 1619
Re: state function mnemonic device
PDTVHUGS, Pressure(P) Density(D) Temperature(T) Volume(V) Enthalpy(H) InternalEnergy(U) GibbsFreeEnergy(G) Entropy(S)
I think Lyndon's went something like this:
If you're under Pressure and Depressed, just watch some TV and get lots of HUGS.
I think Lyndon's went something like this:
If you're under Pressure and Depressed, just watch some TV and get lots of HUGS.
- Sun Feb 09, 2020 6:54 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Law of Conservation Energy
- Replies: 5
- Views: 225
Re: Law of Conservation Energy
Yes, energy is neither created nor destroyed, but it can be transformed or transferred. It is conserved over time.
- Sun Feb 09, 2020 6:50 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: First Law of Themordynamics
- Replies: 4
- Views: 228
Re: First Law of Themordynamics
The First Law of thermodynamics is a "version" of the Law of Conservation of Energy. They're the same thing, but the First Law is adapted for thermodynamic processes.
- Sun Feb 09, 2020 6:45 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Delta U
- Replies: 7
- Views: 392
Re: Delta U
delta U is equal to 0 when temperature is constant. If delta U is 0, and deltaU=q+w, then 0=q+w and when you solve for q then the equation becomes q= -w
- Sun Feb 09, 2020 6:43 pm
- Forum: Calculating Work of Expansion
- Topic: Isobaric and Isochoric
- Replies: 5
- Views: 363
Re: Isobaric and Isochoric
Just remember "iso" means same (equal measurements), "baric" is for pressure, and "choric" is for volume.
- Sun Feb 02, 2020 8:21 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Isolated vs Closed [ENDORSED]
- Replies: 34
- Views: 4083
Re: Isolated vs Closed [ENDORSED]
Open systems allow everything (matter and heat) to go in and out. Closed systems only allow heat to go in and out. Isolated systems don't allow either in or out.
- Sun Feb 02, 2020 8:18 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Test 1
- Replies: 6
- Views: 204
Test 1
How do you know which direction the reaction will go based off of K and Q values?
- Sun Feb 02, 2020 8:16 pm
- Forum: Student Social/Study Group
- Topic: Midterm study
- Replies: 8
- Views: 432
Midterm study
I didn't have Lavelle last quarter for 14A, so I'm not sure how the review sessions are and the amount is overwhelming. Which workshops/drop-ins/review sessions would you suggest? Thank you.
- Sun Feb 02, 2020 8:12 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Purpose
- Replies: 2
- Views: 111
Purpose
What is the purpose of a calorimeter, and how accurate is it?
- Sun Feb 02, 2020 8:05 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: U and H
- Replies: 2
- Views: 113
U and H
How do I know when to use the (U = q - w) equation and when to use the (H = U + PV)?
- Sun Jan 26, 2020 3:42 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Method 3
- Replies: 2
- Views: 146
Method 3
How do you make sure that the reaction is in standard state?
- Sun Jan 26, 2020 3:35 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: ICE
- Replies: 20
- Views: 848
Re: ICE
You use the ICE table when trying to find a missing concentration. Ka and the initial concentration of the reactant are usually given.
- Sun Jan 26, 2020 3:23 pm
- Forum: Phase Changes & Related Calculations
- Topic: Standard State
- Replies: 2
- Views: 182
Standard State
Is the standard state the same for all elements?
- Sun Jan 26, 2020 3:21 pm
- Forum: Phase Changes & Related Calculations
- Topic: Enthalpy w/ Temp
- Replies: 6
- Views: 174
Enthalpy w/ Temp
How does a change in temperature affect enthalpy?
- Sun Jan 26, 2020 3:20 pm
- Forum: Phase Changes & Related Calculations
- Topic: Enthalpy & Spontaneity
- Replies: 4
- Views: 211
Enthalpy & Spontaneity
How is enthalpy related to the spontaneity of a reaction?
- Sun Jan 19, 2020 11:33 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Change in Temperature
- Replies: 2
- Views: 90
Change in Temperature
What happens to equilibrium if the temperature goes higher or lower than 25C?
- Sun Jan 19, 2020 11:24 am
- Forum: Ideal Gases
- Topic: R Constant
- Replies: 7
- Views: 233
R Constant
How do we know which R constant to use in calculation?
- Sun Jan 19, 2020 11:21 am
- Forum: Non-Equilibrium Conditions & The Reaction Quotient
- Topic: Solids and Liquids
- Replies: 6
- Views: 239
Solids and Liquids
Why are solids and liquids disregarded when calculating K and Q?
- Sun Jan 19, 2020 11:20 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: ICE Box
- Replies: 4
- Views: 135
ICE Box
Why is the H2O ignored when creating the ICE box?
- Sun Jan 19, 2020 11:14 am
- Forum: Ideal Gases
- Topic: Topics on Test 1
- Replies: 37
- Views: 1242
Re: Topics on Test 1
Test 1 covers all of chemical equilibrium and acids and bases.
- Sun Jan 19, 2020 11:09 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Titration
- Replies: 1
- Views: 62
Titration
How does titration affect equilibrium?
- Sun Jan 19, 2020 11:02 am
- Forum: Ideal Gases
- Topic: PV=nRT
- Replies: 13
- Views: 609
Re: PV=nRT
It could possibly be used to find the partial pressure of a molecule if you are looking for Kp.
- Sun Jan 19, 2020 10:53 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: K vs Kc
- Replies: 3
- Views: 90
Re: K vs Kc
Both are equilibrium constants. K is the general constant while Kc is the constant denoted when calculating with concentrations, just like how Kp is used when calculating with pressures.
- Sun Jan 19, 2020 10:50 am
- Forum: Identifying Acidic & Basic Salts
- Topic: Identifying salts
- Replies: 4
- Views: 313
Identifying salts
How can I identify a salt in a reaction?
- Sun Jan 19, 2020 10:48 am
- Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
- Topic: Strength of Acids and Bases
- Replies: 1
- Views: 151
Strength of Acids and Bases
How do you know the strength of an acid or a base just by looking at what molecules/atoms it's made of?