Search found 10 matches

by Cesar Martinez 2A
Sun Mar 13, 2016 12:31 pm
Forum: *Cyclohexanes (Chair, Boat, Geometric Isomers)
Topic: Chair Flip
Replies: 2
Views: 396

Re: Chair Flip

The chair flip forces equatorial substtiuents into axial positions and vice versa. This is helpful when determining which chair conformation is most stable. If your largest substituent is in an axial position, you can perform a chair flip to get it into a more stable, equatorial position.
by Cesar Martinez 2A
Sun Mar 06, 2016 11:13 pm
Forum: *Alkanes and Substituted Alkanes (Staggered, Eclipsed, Gauche, Anti, Newman Projections)
Topic: Butane conformations
Replies: 1
Views: 377

Re: Butane conformations

So you can think about stability in this case as which conformation makes it so that the atoms won't bump into each other in space. The less the atoms bump into each other, the more stable the molecule. The more they bump into each other, the more unstable the molecule becomes. Using this, you can t...
by Cesar Martinez 2A
Sun Feb 28, 2016 11:57 pm
Forum: *Alkanes
Topic: Condensed structural formulas
Replies: 1
Views: 284

Re: Condensed structural formulas

Pretty sure there should only be one way per molecule, seeing as how you draw the molecule from left to right. The formula could be written backwards, but that would give you the same molecule, just flipped.
by Cesar Martinez 2A
Sat Feb 13, 2016 4:51 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7951
Views: 1388997

Re: Chemistry Jokes

How can photons be Catholic if they don't even have mass?
by Cesar Martinez 2A
Sun Feb 07, 2016 7:31 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 7951
Views: 1388997

Re: Chemistry Jokes

A bunch of atoms were protesting. A guy walks up and asks them "Are you guys unionized?"

What is avocado's number?
The amount of particles in one guacamole.
by Cesar Martinez 2A
Sun Feb 07, 2016 7:23 pm
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: Midterm 2012 Q: 7A
Replies: 2
Views: 428

Re: Midterm 2012 Q: 7A

I'm not quite understanding how you're getting -2.02 with those values. You're given Ecell=-0.689 and Eanode=0.34 The equation you will use is Ecell=Ecathode-Eanode, where you want to find the value of Ecathode. Rearrange the equation to solve for Ecathode: Ecathode=Ecell+Eanode So, plugging in the ...
by Cesar Martinez 2A
Sun Jan 31, 2016 10:36 pm
Forum: Balancing Redox Reactions
Topic: Basic Solutions
Replies: 1
Views: 310

Re: Basic Solutions

Definitely balance the oxygen first. After that, balance the hydrogen by putting H2O on the other side and the same amount of OH on the side opposite of that. For example: O3 -> O2 Original equation. O3 -> O2 + (H2O) This balances the oxygen on both sides. (2 H2O) + O3 -> O2 + H2O +(2 OH-) Balance t...
by Cesar Martinez 2A
Fri Jan 22, 2016 8:35 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: Entropy Practice Quiz 2014 #6
Replies: 3
Views: 523

Re: Entropy Practice Quiz 2014 #6

So regardless of the size of the molecule, a gas will always have higher entropy than a liquid? Will there ever be a case where a liquid will have higher entropy than a gas? In general, yes. Gases tend to have higher entropy because entropy is essentially the amount of disorder in a molecule or ato...
by Cesar Martinez 2A
Sat Jan 16, 2016 1:18 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Signs for enthalpy
Replies: 3
Views: 555

Re: Signs for enthalpy

Enthalpy is positive when a bond is broken because an energy input is required to break the bond (i.e. heat energy is added to the system from the surrounding-endothermic). The same logic but opposite process is the reason enthalpy is negative when a bond is formed (exothermic). Just going to expan...
by Cesar Martinez 2A
Fri Jan 08, 2016 8:07 pm
Forum: Phase Changes & Related Calculations
Topic: Calculating Enthalpy with Bond Enthalpies
Replies: 2
Views: 560

Re: Calculating Enthalpy with Bond Enthalpies

Yes, it is best to draw out the Lewis structures. It is much easier to see whether bonds remain intact, are created, or are destroyed. The process used to find enthalpy is: 1. Draw the Lewis structures for the molecules before and after the reaction. 2. Write down the bonds that are destroyed from t...

Go to advanced search