Search found 41 matches

Sat Mar 17, 2018 4:38 pm
Forum: Van't Hoff Equation
Topic: 2 Forms
Replies: 1
Views: 173

2 Forms

What are the two different variations of the Van't Hoff Equation and when do we use each one?
Sat Mar 17, 2018 4:30 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: Practice Midterm
Replies: 2
Views: 195

Practice Midterm

From the practice midterm question 6a reads we can expect an endothermic reaction to be favorable at a very hight temp. Why would this be false?
Fri Mar 16, 2018 3:19 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: 14.15 A
Replies: 1
Views: 81

14.15 A

for part a of the question the equation they give is AgBr(s)---->Ag+(aq) + Br-(aq). It then lists the cathode reaction as Ag+(aq) + e- ---->Ag(s). Why does the AgBr turn into just Ag in this case?
Fri Mar 16, 2018 3:07 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: 14.13 B
Replies: 3
Views: 125

14.13 B

This question you are supposed to write the cell diagram for the equation Ce^4+(aq) + I^-(aq)---> I2(s) + Ce^3+(aq) the solutions manual has the cell diagram as Pt(s)|I-(aq)|I(s)||Ce4+(aq),Ce3+(aq)|Pt(s). Why do we need the Pt at the anode I thought solids, in this case I, could be used as electrodes.
Thu Mar 15, 2018 8:15 pm
Forum: *Nucleophiles
Topic: Final
Replies: 1
Views: 270

Final

What should we know about nucleophiles for the final exam?
Thu Mar 15, 2018 4:42 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Slow/Fast Step
Replies: 2
Views: 98

Slow/Fast Step

Is it possible to determine what step is the slow step and what step is passed if we are only given the rate law?
Thu Mar 15, 2018 4:39 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Reaction Profiles
Replies: 1
Views: 74

Reaction Profiles

Could we be asked to draw a reaction profile on the final exam?
Wed Mar 14, 2018 6:43 pm
Forum: General Rate Laws
Topic: Test 3 #3
Replies: 1
Views: 104

Test 3 #3

The rate of C2 gas consumption in this reaction is constant throughout and is given as 0.250 M/s. If you reaction vessel starts with 0.35M of ABC, how long will it take to get to 24.00M of ABC? The equation give is AB+C-->ABC. Can someone explain how they did this please.
Mon Mar 12, 2018 2:22 pm
Forum: *Alcohols
Topic: Functional Groups [ENDORSED]
Replies: 2
Views: 331

Functional Groups[ENDORSED]

Will questions involving functional groups be included on the final exam?
Mon Mar 05, 2018 3:24 pm
Forum: Calculating Work of Expansion
Topic: Calculating Work
Replies: 1
Views: 84

Calculating Work

When pressure is held constant what equation do you use to calculate the work done?
Mon Mar 05, 2018 3:17 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Termolecular Reactions
Replies: 2
Views: 124

Termolecular Reactions

In lecture it was said that termolecular reactions are rare. If this is the case could we still be given an example of one on a test or do we not have to worry about them at all?
Mon Mar 05, 2018 2:26 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Rate Determining and Rate Limiting [ENDORSED]
Replies: 1
Views: 79

Re: Rate Determining and Rate Limiting[ENDORSED]

Yes rate determining and rate limiting can be thought of as the same thing.
Mon Mar 05, 2018 2:18 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Test 2
Replies: 4
Views: 176

Re: Test 2

I'm still unsure on this problem as well, after you find delta g how would you find the standard potential of the cell?
Mon Mar 05, 2018 2:13 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Which Step is Slower?
Replies: 8
Views: 208

Re: Which Step is Slower?

The slowest step in a reaction is the one with the higher activation energy.
Mon Mar 05, 2018 2:11 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Molecularity
Replies: 3
Views: 100

Molecularity

Can someone clarify what exactly molecularity is.
Mon Mar 05, 2018 2:08 pm
Forum: General Rate Laws
Topic: Order?
Replies: 3
Views: 130

Order?

How do you determine what order a reaction is?
Mon Mar 05, 2018 2:05 pm
Forum: General Rate Laws
Topic: Clarification Question
Replies: 1
Views: 85

Clarification Question

In lecture I wrote this down, Rate=-1/a*d[A]/dt=k[A]^2 and then the next thing was just -d[A]/dt=k[A]^2. What happens to the -1/a?
Wed Feb 21, 2018 9:18 pm
Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
Replies: 3
Views: 304

What exactly does it mean when a system is adiabatic?
Wed Feb 21, 2018 9:18 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: 14.57
Replies: 2
Views: 93

14.57

In this problem it says the reduction potential of water is -0.42V, is this somewhere in the appendix or are we just supposed to have this memorized?
Tue Feb 20, 2018 8:10 pm
Forum: Balancing Redox Reactions
Topic: 14.1 D
Replies: 3
Views: 150

14.1 D

In this question you are supposed to balance the redox equation the answer reads, 8H+ + Cr2O7^2- + 3C2H5OH---> 2Cr^3+ + 3C2H4O + 7H2O. why do you need the 3 in front of C2H5OH and C2H4O
Tue Feb 20, 2018 7:45 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Anode/Cathode
Replies: 2
Views: 80

Anode/Cathode

Which reaction relates to which, is the reduction reaction the anode and oxidation is the cathode or is it the other way around?
Tue Feb 20, 2018 7:26 pm
Forum: Balancing Redox Reactions
Topic: Exceptions in Halogens
Replies: 1
Views: 66

Re: Exceptions in Halogens

I believe it depends on the molecule the halogen is in for example in HClO Cl would have an oxidation state of +1
Tue Feb 20, 2018 7:22 pm
Forum: Balancing Redox Reactions
Topic: Oxidation States
Replies: 2
Views: 111

Oxidation States

What elements oxidation states are most important to memorize?
Sun Feb 11, 2018 9:33 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Sublimation
Replies: 3
Views: 209

Sublimation

I was working on the practice midterm and on question 2C it mentions the enthalpy of sublimation of graphite. What exactly is enthalpy of sublimation and when do we use it?
Wed Feb 07, 2018 9:09 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Spontaneity
Replies: 9
Views: 371

Spontaneity

What value indicates spontaneity is it a positive or negative delta g
Wed Jan 24, 2018 3:36 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: What are the types of calorimeters we learned about/ covered in class?
Replies: 4
Views: 192

Re: What are the types of calorimeters we learned about/ covered in class?

A coffee cup calorimeter involves using a styrofoam cup so it could be referred to as a styrofoam cup calorimeter but I don't think Dr. Lavelle has ever called it this.
Wed Jan 24, 2018 3:32 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Hess's Law [ENDORSED]
Replies: 7
Views: 274

Hess's Law[ENDORSED]

For questions involving Hess's law are we going to be given the reactions involved or are we going to have to write them ourselves?
Tue Jan 23, 2018 6:24 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Concepts and Equations
Replies: 2
Views: 80

Concepts and Equations

Is there a specific reason the equation H=U-PV is not on the constants and equations sheet? Should we just simply memorize this?
Wed Jan 17, 2018 10:05 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: 8.25
Replies: 2
Views: 105

8.25

In this problem the temperatures are given in celsius but in the solution we use them in units of kelvin without adding 273. Why is this possible?
Wed Jan 17, 2018 9:32 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: 8.19(b)
Replies: 1
Views: 92

8.19(b)

"What percentage of heat is used to raise the temperature of the water? (See Table 8.2)" the solution manual has you divid 1.30*10^5 by our answer from part a where does this number come from?
Sat Dec 09, 2017 11:20 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: Strengths of Acids
Replies: 2
Views: 312

Re: Strengths of Acids

If we have something like HClO2 and HClO the additional O in HClO2 increases the electronegativity and helps to pull the electron in H out of the H-O bond. Hope this helps a little bit.
Sat Dec 09, 2017 3:32 pm
Forum: Electronegativity
Topic: Kr
Replies: 3
Views: 235

Kr

Does Kr have a greater first ionization than Mg because its valence shell is complete? I figured since Mg is much smaller it would have a larger first ionization energy.
Sat Dec 09, 2017 3:25 pm
Forum: Lewis Acids & Bases
Topic: 4C
Replies: 2
Views: 168

4C

In the compound [NiBr3(CO)2] why is Ni3+ the Lewis acid?
Sat Dec 09, 2017 3:20 pm
Forum: Administrative Questions and Class Announcements
Topic: Final [ENDORSED]
Replies: 6
Views: 505

Re: Final[ENDORSED]

Probably pretty important to touch up and chapters involving wavelength, frequency, and energy. This was a major topic we covered in the course.
Fri Dec 08, 2017 11:18 pm
Forum: Bronsted Acids & Bases
Topic: 12.115
Replies: 1
Views: 162

Re: 12.115

Nitrous acid acts like a strong acid because its conjugate base is weaker than the acetate ion that is present. This presence of acetate will shift the reaction towards the products which will increase the Ka of nitrous acid causing it to act like a strong base. I'd assume that it is the same for pa...
Fri Dec 08, 2017 11:05 pm
Forum: Conjugate Acids & Bases
Topic: 12.47
Replies: 2
Views: 233

12.47

Are we expected to memorize pKa and Pkb values because this problem made it seem that way.
Fri Dec 08, 2017 12:51 am
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: 12.21
Replies: 2
Views: 121

12.21

Might be a dumb question but in the solutions manual it says Kw=[H3O+][OH-]=1.0*10^-14. Where does this value come from?
Fri Dec 08, 2017 12:45 am
Forum: Lewis Acids & Bases
Topic: 12.17
Replies: 2
Views: 152

12.17

How can you determine if an oxide is acidic basic or amphoteric. The examples from this question are BaO, SO3, As2O3, Bi2O3
Mon Nov 27, 2017 12:23 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Q [ENDORSED]
Replies: 7
Views: 488

Q[ENDORSED]

Today in lecture Dr. Lavelle was talking about finding Q, what does Q actually represent I was a little confused.
Wed Nov 15, 2017 12:16 pm
Forum: Hybridization
Topic: Notation
Replies: 6
Views: 271

Notation

Can someone explain the notation that involves px1 py1 and pz1. In what cases do we write the configuration like this.
Sun Nov 05, 2017 11:38 am
Forum: Administrative Questions and Class Announcements
Topic: Class Schedule
Replies: 1
Views: 123

Class Schedule

Is there going to be class held on this coming Friday even though it is a holiday?

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