Search found 23 matches

Thu Mar 10, 2016 12:25 am
Forum: *Alcohols
Topic: Priorities after functional group
Replies: 1
Views: 431

Priorities after functional group

I know that functional groups get priority with numbering. However, let's say after you number the carbons of a cycloalkene and the functional group is at carbon 1, there's a double bond two carbons to the right and a substituent one carbon to the left. Which way would be the correct way to number t...
Sun Mar 06, 2016 8:59 pm
Forum: *Alkanes
Topic: amyl
Replies: 1
Views: 374

amyl

Is pentyl always exchanged with amyl when naming an organic molecule? Are they interchangeable?
Sun Mar 06, 2016 8:57 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: Cv vs Cp
Replies: 3
Views: 707

Cv vs Cp

When something has a constant volume and constant pressure, do you use Cv or Cp in calculations?
Mon Feb 29, 2016 5:45 pm
Topic: Two step electrophilic addition reaction
Replies: 3
Views: 582

(an example is on the bottom of page 87)
When an electrophilic addition reaction is two steps with the positively charged atom binding first and the negatively one binding second, how do we know where the two different atoms bind (on which side of the double bond)? Does it matter?
Thu Feb 25, 2016 12:32 am
Forum: *Constitutional and Geometric Isomers (cis, Z and trans, E)
Topic: Z and E when naming alkenes
Replies: 2
Views: 436

Z and E when naming alkenes

Do we always use Z or E when naming a compound with a double bond? I can't seem to figure out when exactly we use Z and E in naming. Also, on 1.26 in the organic chem book homework problem, I don't understand why it is E and not Z.
Wed Feb 17, 2016 5:36 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: K = Kf/Kr
Replies: 1
Views: 54127

K = Kf/Kr

I'm confused on why K=kforward/kreverse. If the reaction is A -> B+C , isn't K=[B][C]/[A]? and kforward would equal [A] and kreverse would equal [B][C]. So wouldn't K=kreverse/kforward?
Tue Feb 09, 2016 12:04 am
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Ka
Replies: 1
Views: 417

Ka

When a question asks to find Ka, does it imply that H+ is being formed in the reaction? (I am referring specifically to question 8 on the 2014 Winter Midterm)
Tue Feb 09, 2016 12:01 am
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: 14.119
Replies: 1
Views: 419

14.119

In the first stage of the reaction, why is H20+O2 reduced when it is not even in the problem? I thought the oxidation/reduction of water was only considered in electrolysis.
Mon Feb 08, 2016 8:58 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: H kJ/mol or just kJ
Replies: 1
Views: 1777

H kJ/mol or just kJ

When finding delta H, how do we know whether to put the units as kJ or kJ/mol. Also, when dividing by the amount of moles, how do we know how much do divide by?
Mon Feb 01, 2016 3:16 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: K>1 vs K<1
Replies: 1
Views: 2151

K>1 vs K<1

How come when K>1 (there is a higher concentration of products than reactants), the reaction favors the products? I would have thought that because there are more products, the reverse reaction would be favored in order to balance the products and reactants.
Mon Jan 25, 2016 10:23 am
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: Comparing Entropies
Replies: 1
Views: 299

Comparing Entropies

When comparing entropies of elements, which factors should be looked at first? Complexity, state, or amount of the molecule?
For example, would a 1 mol of a more complex gas have more or less entropy than 2 mol of a less complex gas?
Mon Jan 18, 2016 9:24 pm
Forum: Calculating Work of Expansion
Topic: Internal energy and work
Replies: 2
Views: 495

Internal energy and work

In equations where we calculate the internal energy, how do we know if there is work done? Can we tell just by looking at the chemical reaction?
Fri Jan 15, 2016 2:11 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 8199
Views: 1430046

Re: Chemistry Jokes

"I'd make a chemistry joke but all the good ones Argon"
Sun Jan 10, 2016 12:32 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Heat Capacity Units
Replies: 2
Views: 452

Heat Capacity Units

Are the standard units of heat and the specific heat capacity measured in Joules or kilojoules?
Wed Dec 02, 2015 11:02 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: When to use Henderson Hasselbalch
Replies: 2
Views: 483

Re: When to use Henderson Hasselbalch

Does it make a difference whether we use Henderson Hasselbalch or an ICE box?
Sun Nov 22, 2015 5:53 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: ICE table when calculating for pH
Replies: 3
Views: 906

Re: ICE table when calculating for pH

pH + pOH =14. If you are given the pOH, you calculate the pH with the equation: pH = 14 - pOH
Thu Nov 12, 2015 11:45 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Solids
Replies: 1
Views: 166

Solids

Are solids never included when calculating equilibrium constants?
Sun Nov 08, 2015 11:23 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 8199
Views: 1430046

Re: Chemistry Jokes

"Are you Na?
Because you're so-dium fine doe!!"
Thu Oct 29, 2015 11:05 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Electron distortions
Replies: 2
Views: 398

Electron distortions

What exactly are electron distortions? I know that electron distortions increase with the size of an atom but I am confused what exactly they are.
Sat Oct 24, 2015 10:21 pm
Forum: Hybridization
Topic: Hybridization vs. Hybrid Orbitals
Replies: 1
Views: 388

Hybridization vs. Hybrid Orbitals

In a question, is asking for the hybridization of a molecule and asking for the hybrid orbitals of a molecule the same thing?
Thu Oct 15, 2015 11:45 pm
Forum: Lewis Structures
Topic: Lewis Structure Stability
Replies: 3
Views: 685

Re: Lewis Structure Stability

Does the order in which the elements are listed in the molecule name give any clue as to how the Lewis structure should be drawn? For example, in an element such as CH2COCH3-, can we gain a general idea of how the structure should look solely based on the order of the elements given?
Fri Oct 09, 2015 10:03 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Energy Levels of d and s
Replies: 3
Views: 573

Re: Energy Levels of d and s

If the 3d subshell would fill up after the 4s subshell, if an electron was removed from an atom, would it be removed from the 4s subshell (which is on the outermost shell) or the 3d subshell (which has the higher l value)?
Wed Sep 30, 2015 5:08 pm
Forum: Significant Figures
Topic: All students read this sig fig post [ENDORSED]
Replies: 133
Views: 17383

Re: All students read this sig fig post[ENDORSED]

Can we just round off to the smallest amount of sig figs in the given numbers in the problem? Generally that's what I do (it's normally 3-4 sig figs), but I'm not sure if that's what he wants.