## Search found 17 matches

Sat Mar 12, 2016 10:09 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Electrode
Replies: 1
Views: 301

### Electrode

Is an electrode always a solid?? Because I did not think that there could be a hydrogen electrode.
Sun Mar 06, 2016 9:20 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Ethane vs Ethene
Replies: 1
Views: 318

### Re: Ethane vs Ethene

Ethane has single C-C bonds while, ethene has double C-C bonds. Therefore, ethane has more freedom, greater range of movement. When the range of movement increases for a molecule so does the heat capacity.
Sun Feb 28, 2016 8:02 pm
Forum: *Free Energy of Activation vs Activation Energy
Topic: 2nd Quiz of Quiz 2 Prep (NUMBER 11)
Replies: 1
Views: 438

### 2nd Quiz of Quiz 2 Prep (NUMBER 11)

The rate constant for the reaction A--> B is 25/min at 298K and 35/min at 350K. Calculate the value of the rate constant at 770K. Give your answer in /min. I calculated the activation energies for both temperatures and they are different. I thought that activation energy is independent of temperatur...
Sun Feb 28, 2016 7:54 pm
Forum: *Alkanes
Topic: Determining CIS or TRANS
Replies: 3
Views: 427

### Determining CIS or TRANS

What if you were given :

Cl CH2CH3
\ /
C = C
/ \
Cl CH3

Would this be cis or trans??

Cl & Cl are attached to Carbon 1 ; CH2CH3 and CH3 are attached to Carbon 2
Sun Feb 28, 2016 7:45 pm
Forum: *Alkanes
Topic: Quiz 3 Preparation #5
Replies: 5
Views: 532

### Re: Quiz 3 Preparation #5

Iodine gets lower numbering than Bromine because Iodine has higher priority. Priority is based on the atomic number bound to the carbon.
highest I>Br
Sun Feb 21, 2016 9:40 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: Reverse reaction of k
Replies: 2
Views: 472

### Re: Reverse reaction of k

The units of k and k prime also depend on the order of the reaction. So there is no absolute units for k and k prime for all reactions. If your reaction is first order then k and k prime would have the unit /sec (s^-1); zero order units M/s; 2nd order units L/mol x S (M^-1 x S^-1)
Sun Feb 14, 2016 9:11 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: HW 15.49
Replies: 5
Views: 568

### HW 15.49

For part b of this question it asks for the rate law and the answer in the solutions manual says that the rate for step 2 equals k2[HBR][HOBR] however HOBR is an intermediate. I thought you weren't suppose to include the intermediate in the rate laws???
Sun Feb 07, 2016 7:46 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Negative Cell Potential
Replies: 1
Views: 306

### Negative Cell Potential

When would you purposely have a negative value for E naught cell???
Sun Jan 31, 2016 2:35 pm
Forum: Administrative Questions and Class Announcements
Topic: Video Competition
Replies: 66
Views: 24955

### Re: Video Competition

Is there a time limit on the video? Also, do we have to post the video in a different format for each person in the group like last quarter??
Sun Jan 24, 2016 1:40 pm
Forum: Thermodynamic Systems (Open, Closed, Isolated)
Topic: Work done on an isolated system
Replies: 1
Views: 335

### Re: Work done on an isolated system

Since the system is being compressed by the piston, the change in volume is a negative value and since work is -PV, the change in work will become positive. So yes you are correct.
Sat Jan 16, 2016 4:48 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Easy way to remember state functions
Replies: 1
Views: 458

### Re: Easy way to remember state functions

Thanks for pointing that out! I would also like to add the state property (Density) to the upper case list and heat (q) to the not state property list
Therefore,
State properties (U, P, V, T, Density(ρ or D), C(heat capacity) )
Not state properties WORK (w) and HEAT (q)
Sun Jan 10, 2016 7:49 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Molar Heat Capacity vs Specific Heat Capacity
Replies: 1
Views: 364

### Re: Molar Heat Capacity vs Specific Heat Capacity

if you are trying to find the amount of heat required to raise temp of 1g of a substance by 1 degree C --> specific heat capacity kJ. C^-1 g^-1

if you are trying to find the amount of heat required to raise temp of 1mol of a substance by 1 degree C --> molar heat capacity J.K^-1 mol^-1
Thu Nov 19, 2015 5:01 pm
Forum: Resonance Structures
Topic: Resonance Video Submission
Replies: 2
Views: 540

### Resonance Video Submission

drawing lewis structures with resonance, delocalized bonds, ex of sulfate

Chem (14A) Community Video.m4v [ 262.49 MiB | Viewed 540 times ]

Sun Oct 25, 2015 11:38 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Lewis Structures
Replies: 1
Views: 331

### Re: Lewis Structures

although there are 5 regions of electron density, the shape is linear because the 3 lone pairs surrounding the central iodine are all 120 degrees apart from each other making the electron repulsion cancel out and making the molecule linear and polar
Sun Oct 18, 2015 5:25 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: electron configuration for Bi^3+
Replies: 1
Views: 7017

### Re: electron configuration for Bi^3+

With Xe, the electron configuration of Bi3+ would be [Xe]4f^14 5d^10 6s^2
Sat Oct 10, 2015 10:52 pm
Forum: Properties of Electrons
Topic: Quantum Numbers
Replies: 2
Views: 433

### Re: Quantum Numbers

for example if you are given n=2, you know that l can only equal the values 0 and 1
and when l=0 this corresponds to the s-orbital and when l=1 it will correspond to the p-orbital as so on...
Sat Oct 10, 2015 10:42 pm
Forum: Trends in The Periodic Table