Hi Dr. Lavelle,
Thanks for dedicating so much passion and time in teaching us Chem 14B. You really made my winter quarter memorable. I really enjoyed Friday's jokes and the numerous resources available for students.
Search found 13 matches
- Sun Mar 19, 2017 8:20 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Saying Thank You to Dr. Lavelle
- Replies: 490
- Views: 570584
- Sun Mar 12, 2017 8:49 pm
- Forum: *Alkanes and Substituted Alkanes (Staggered, Eclipsed, Gauche, Anti, Newman Projections)
- Topic: Dihedral Angle
- Replies: 1
- Views: 620
Dihedral Angle
I am having difficulty seeing what the dihedral angle is?
- Sun Mar 05, 2017 4:46 pm
- Forum: *Electrophilic Addition
- Topic: Reaction Profiles
- Replies: 2
- Views: 1401
Reaction Profiles
Why is it that in transition states and intermediates, the energy is higher than in reactants and products?
- Sun Feb 26, 2017 2:49 pm
- Forum: *Nucleophiles
- Topic: Basic Mechanisms
- Replies: 1
- Views: 462
Basic Mechanisms
When writing basic mechanisms, why do we draw the arrows from the nucleophiles to the electrophiles?
- Sun Feb 19, 2017 4:33 am
- Forum: First Order Reactions
- Topic: Half Life
- Replies: 1
- Views: 537
Half Life
Why is the half-life of a first order reaction independent of the initial concentration?
- Mon Feb 06, 2017 11:30 am
- Forum: Balancing Redox Reactions
- Topic: 14.11 (d)
- Replies: 1
- Views: 511
14.11 (d)
Write the half-reactions and the balanced equation for the cell reaction for each of the following galvanic cells: (d) Pt(s)|O2(g)|H+(aq)||OH-(aq)|O2(g)|Pt(s) If you look at the solution manual, why is the anode reaction the one with the larger Eknot? I thought the cell potential had to be positiv...
- Sun Feb 05, 2017 3:52 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Standard Potentials in Electrochemical Series
- Replies: 1
- Views: 371
Standard Potentials in Electrochemical Series
Why is it more strongly reducing when the standard potential is low/negative and vice versa?
- Thu Jan 26, 2017 8:56 am
- Forum: Concepts & Calculations Using Second Law of Thermodynamics
- Topic: Self Test 9.17A
- Replies: 1
- Views: 439
Self Test 9.17A
Determine delta S,delta Ssurr, and delta Stot for (a) the reversible, isothermal expansion and (b) the isothermal free expansion of 1.00 mol of ideal gas molecules from 10.00 atm and 0.200 L to 1.00 atm and 2.00 L at 298 K. Why can we disregard the pressures ( 10 atm and 1 atm) when solving this ...
- Sun Jan 22, 2017 11:20 am
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Example 8.7 on Section 8.13
- Replies: 1
- Views: 439
Re: Example 8.7 on Section 8.13
Normally, the equation of delta H = q/n. The enthalpy change is usually referred to as the the enthalpy change PER mole. However, in this question, the moles of C6H6 is 2, not 1. Therefore, we must multiply 2 * q/n.
- Sat Jan 21, 2017 9:48 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Homework Problem 8.41
- Replies: 2
- Views: 587
Re: Homework Problem 8.41
At 0 degrees Celsius, there is a phase change because it has a mixture of ice and water. Therefore we must add that to the temperature change at 0 Celsius.
- Sat Jan 21, 2017 9:29 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Homework chapter 8 #3 part a
- Replies: 1
- Views: 418
Re: Homework chapter 8 #3 part a
The volume of an object is length * width * height. In this particular case, we are trying to find the volume of a cylinder shaped object. The length * width portion of the volume is the cross section area of the cylinder, which is just the area of a circle (pir^2). We are given the diameter (3 cm),...
- Sat Jan 21, 2017 9:12 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Homework Question: 8.49
- Replies: 1
- Views: 484
Re: Homework Question: 8.49
The equation is delta U= q + w.
q= -318
w= -2.48
So the book is correct; you add q+w together to get -320 ( you subtracted w from q).
q= -318
w= -2.48
So the book is correct; you add q+w together to get -320 ( you subtracted w from q).
- Sat Jan 14, 2017 3:42 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Hw 8.75b
- Replies: 1
- Views: 380
Hw 8.75b
8.75 Use the bond enthalpies in Tables 8.6 and 8.7 to estimate the reaction enthalpy for (a) N2(g)+ 3 F2(g) --> 2 NF3(g) (b) CH3CHCH2(g) + H2O(g) --> CH3CH(OH)CH3(g) (c) CH4(g)+ Cl2(g) -->CH3Cl(g)+ HCl(g) How am I supposed to know which mean bond enthalpies to use for CH3CHCH2 and CH3CH(OH)CH3?