## Search found 14 matches

Fri Mar 11, 2016 7:10 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Rate constant and Ea
Replies: 1
Views: 323

### Rate constant and Ea

If the rate constant is decreased, will Ea increase? Is the presence of a catalyst the only thing that effects Ea?
Mon Mar 07, 2016 3:29 pm
Forum: *Cyclohexanes (Chair, Boat, Geometric Isomers)
Topic: Importance of Cis and Trans Isomers
Replies: 1
Views: 304

### Re: Importance of Cis and Trans Isomers

Some cis and trans isomers are more stable, so they will have preferred conformations. For example, the trans equatorial chair conformation for cyclohexanes is the most stable form. Especially with big substituents, the energy difference between trans and cis will be greater, and so most of the cycl...
Wed Mar 02, 2016 8:24 pm
Forum: *Cycloalkenes
Topic: naming compounds
Replies: 2
Views: 376

### Re: naming compounds

Yes, try to recognize the difference between iso and sec, and tert and neo. Once you recognize what the common names are, you can use them while naming compounds!
Thu Feb 25, 2016 3:18 pm
Forum: *Alkanes
Topic: Tert- structures
Replies: 1
Views: 219

### Tert- structures

Why are tert structures called tert if they are connected to four carbons? For example, tert-butyl is connected to four carbons?
Thu Feb 18, 2016 10:58 pm
Forum: General Rate Laws
Topic: Rate Constant K
Replies: 2
Views: 527

### Re: Rate Constant K

First, you must find what order the reaction is. From there, you can plug in information and solve for k as long as you are given information on initial concentrations, final concentration, and time. You can also find k using half life equations as long as you know the order.
Sun Feb 14, 2016 4:44 pm
Forum: Method of Initial Rates (To Determine n and k)
Topic: Equation to find k when there's more than 1 reactant
Replies: 2
Views: 431

### Re: Equation to find k when there's more than 1 reactant

We assume B and C's initial concentrations are so large that any changes in their concentration will not change the overall concentrations of B and C. We are going to observe A's concentration and so we don't assume its initial concentration is large. Any changes in A's concentration would be observ...
Wed Feb 10, 2016 12:10 am
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: E as a Path Function
Replies: 1
Views: 418

### Re: E as a Path Function

Eo is the potential difference at standard conditions allowing us to add and subtract them like Hess's law. E, however, is the cell potential when not at standard conditions and is affected by other variables such as concentrations of products and reactants. That is why E is not a state function whe...
Fri Feb 05, 2016 10:26 am
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: How to calculate Q in Nernst Equation
Replies: 1
Views: 464

### Re: How to calculate Q in Nernst Equation

To find Q, you do not look at the individual half reactions. You have to look at the combined, overall redox reaction in order to determine Q.
Mon Feb 01, 2016 11:59 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Textbook problem 14.11 e)
Replies: 1
Views: 276

### Textbook problem 14.11 e)

The back of the book says the anode is: Sn4+ (aq) + 2e- -> Sn2+ (aq). Anodes are associated with oxidation, but wouldn't this be reduction since the product is gaining electrons? Also, why are the two half reactions flipped in the balanced equation?
Sat Jan 30, 2016 11:46 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Electromotive
Replies: 1
Views: 276

### Re: Electromotive

"i" stands for current, so the electromotive force is the limit as the current approaches 0.
Mon Jan 25, 2016 8:15 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: Values for Cv and Cp
Replies: 1
Views: 243

### Values for Cv and Cp

In the Constants and Formulas page, Cv=(3/2)R, but in the solution for 9.13, Cv=(5/2)R. How do you know which value to use?
Sat Jan 23, 2016 2:25 pm
Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
Topic: Units
Replies: 1
Views: 302

### Units

I am doing the quiz prep from 2011, and for number 9, it says to calculate standard reaction entropy using standard molar entropies. The answer has units of J/K*mol, but I thought standard reaction entropies are just J/K. Why is there a 1/mol in the units of the answer?
Tue Jan 19, 2016 8:15 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: Energy States and Degeneracy
Replies: 1
Views: 194

### Energy States and Degeneracy

How do you determine the degeneracy and the amount of different energy states there are? For example, are there any key words which hint that the system has two, three, or four states? When given a molecule, how can you determine the degeneracy?
Fri Jan 08, 2016 2:34 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Breaking Double Bonds
Replies: 1
Views: 285

### Breaking Double Bonds

Why is it necessary to break both bonds in a double bond rather than just break one when doing bond enthalpy problems?