## Search found 10 matches

Mon Mar 13, 2017 12:59 pm
Forum: *Cyclopropanes and Cyclobutanes
Topic: Torsional Strain
Replies: 2
Views: 783

### Re: Torsional Strain

Yes—torsional strain is a direct result of bonds on adjacent atoms being eclipsed. And yes, it is most prominent in planar conformations, as non planar conformations exist to reduce as much torsional strain as possible. Many non planar conformations can still experience torsional strain, but not nea...
Sun Mar 05, 2017 8:35 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Practice Problems for Quiz #3
Replies: 1
Views: 308

### Re: Practice Problems for Quiz #3

Quiz 3 covers material from 15.11 onward, which corresponds to the problems listed in the course reader from 15.61 onward. As far as the Intro to Organic Chemistry textbook goes, all of the listed problems in the course reader for chapter 4 are fair game, along with 1, 5a, 4b, 6b, 9,10,13a and b, 14...
Sun Feb 26, 2017 9:20 pm
Forum: *Organic Reaction Mechanisms in General
Topic: Lines in Lewis Structures
Replies: 2
Views: 2888

### Lines in Lewis Structures

Could someone explain what the bolded and striped lines mean in Lewis structures? An example of this can be found on page 82 of the course reader and page 149 of the intro to organic chemistry book.
Sun Feb 19, 2017 9:51 pm
Forum: General Rate Laws
Topic: rate of a reaction
Replies: 2
Views: 4860

### Re: rate of a reaction

To calculate the rate here, you must divide the change in concentration (units=M) by the change in time (units=s). The change in concentration is 0.5-0.45=0.05M. The change in time is 0.1s. 0.05M/0.1s=0.5M/s, so the answer is a.
Mon Feb 13, 2017 3:30 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: How do you know which is the anode and which is the cathode?
Replies: 3
Views: 467

### Re: How do you know which is the anode and which is the cathode?

Thanks. In the case of Q8 the Winter 2014 Midterm, though, how come the one with the more positive value is the anode?
Sun Feb 12, 2017 9:19 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: How do you know which is the anode and which is the cathode?
Replies: 3
Views: 467

### How do you know which is the anode and which is the cathode?

I know that left side is associated with the anode and oxidation, while the right is associated with the cathode and reduction, but how do you tell them apart when you are only given the elements involved? For example, Q8 on the Winter 2016 Midterm only mentions that a silver electrode is placed int...
Sun Feb 05, 2017 9:26 pm
Forum: Phase Changes & Related Calculations
Topic: Balancing Equations/When To Use Integers and When Not To?
Replies: 3
Views: 434

### Re: Balancing Equations/When To Use Integers and When Not To?

I believe that fractions are only used to make calculations easier. For example, the mole ratio of reactants to products may be 2 mol reactant forms 3 mol product (2:3), but the question may ask you about "what happens when 1 mol of reactant...?", therefore, you may want to change the coef...
Thu Jan 26, 2017 7:47 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: W versus S
Replies: 2
Views: 365

### Re: W versus S

Simply speaking, S is entropy, a measure of disorder. A low value of S means the level of disorder is small, while a high value of S means the level of disorder is high. One way to calculate S is the Boltzmann formula, which is S=klnW. W is the number of possible arrangements (in the case of a molec...
Sun Jan 22, 2017 6:07 pm
Forum: Phase Changes & Related Calculations
Topic: Reversible vs. irreversible processes
Replies: 2
Views: 338

### Reversible vs. irreversible processes

Could someone please explain the difference between reversible and irreversible processes? Also, what is the significance of this in the types of problems we are doing?
Sun Jan 15, 2017 4:32 pm
Forum: Calculating Work of Expansion
Topic: Comparing the amount of work done
Replies: 1
Views: 293

### Re: Comparing the amount of work done

When comparing amounts of work done, you can think of it in terms of the absolute value. So yes, -343 J is more work than +120 J. See example 8.2 in the textbook.