Search found 28 matches

by Tara_Hekmati_3B
Mon Mar 13, 2017 3:12 pm
Forum: *Alkenes
Topic: Naming an Alkene
Replies: 1
Views: 480

Naming an Alkene

Let's say the name of a certain Alkene is 1,2,3,4,5-pentamethylcyclopenta-1,3-diene. What is the use of using diene in this name? Is this name the same as naming it 1,2,3,4,5-pentamethylcyclopent-1,3-ene?
by Tara_Hekmati_3B
Mon Mar 06, 2017 4:43 pm
Forum: *Alkanes
Topic: drawing line structures
Replies: 2
Views: 587

drawing line structures

Are there multiple ways of drawing the same, correct line structure?
Does it matter whether you start the first diagonal line from the top or bottom?
by Tara_Hekmati_3B
Mon Mar 06, 2017 4:42 pm
Forum: *Electrophilic Addition
Topic: Transition step
Replies: 3
Views: 1595

Transition step

Is the slow step in electrophilic addition always the first step or the step with the highest activation energy barrier?
by Tara_Hekmati_3B
Tue Feb 28, 2017 2:16 pm
Forum: *Alkanes
Topic: Naming [ENDORSED]
Replies: 93
Views: 16723

Naming [ENDORSED]

How do you determine where to put the dashes within the name of the organic compound? I think there are several instances where you would use one, but I just wanted some clarification.
by Tara_Hekmati_3B
Wed Feb 22, 2017 6:30 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Midterm Q4.C
Replies: 2
Views: 524

Midterm Q4.C

This question asks us to write the cell diagram notation for the redox reaction, and I was told the order didn't matter for the components of the cell. I put the anode on the left of the cell diagram and the cathode on the right, but the components of the redox reaction are apparently in the wrong o...
by Tara_Hekmati_3B
Thu Feb 16, 2017 8:36 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 9651
Views: 3638687

Re: Post All Chemistry Jokes Here

Want to hear a joke about nitric oxide?
*(yeah I do)*
NO
by Tara_Hekmati_3B
Mon Feb 13, 2017 6:50 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: 14.11 d)
Replies: 2
Views: 583

Re: 14.11 d)

O2 (g) --> OH- (aq) Basically when you look at this half reaction you want to try to balance the oxygens on both sides because there are two on the left and one on the right. You try doing this by doubling the about of OH-. Now you have... O2 (g) --> 2OH- (aq) Then you want to balance the hydrogens ...
by Tara_Hekmati_3B
Tue Feb 07, 2017 12:27 am
Forum: Work, Gibbs Free Energy, Cell (Redox) Potentials
Topic: What is n? [ENDORSED]
Replies: 8
Views: 1878

What is n? [ENDORSED]

Sometimes n represents the number of electrons in the half reaction, but other times it is the change in the moles throughout the reaction. Could it be either or is it really just one? If you are not told to find the half reactions of the redox equation, do you have to find them anyway to find n if ...
by Tara_Hekmati_3B
Sun Feb 05, 2017 10:29 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 9651
Views: 3638687

Re: Post All Chemistry Jokes Here

Working in an electrochemistry lab seems to show great potential.
by Tara_Hekmati_3B
Sun Feb 05, 2017 12:45 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Cell Diagram
Replies: 2
Views: 444

Cell Diagram

When writing a cell diagram, I understand that the anode is written before the cathode, but in what order do the products and reactants have to be written? When do you use commas instead of vertice lines?
by Tara_Hekmati_3B
Sun Feb 05, 2017 12:42 am
Forum: Third Law of Thermodynamics (For a Unique Ground State (W=1): S -> 0 as T -> 0) and Calculations Using Boltzmann Equation for Entropy
Topic: Entropy
Replies: 1
Views: 482

Entropy

Why is it that at 0 K the entropy of a crystal becomes zero? What does this temperature have to do with the crystals structure?
by Tara_Hekmati_3B
Tue Jan 24, 2017 4:40 pm
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: change in entropy
Replies: 1
Views: 401

change in entropy

Hi.
If delta S of a reversible system= q(reversible)/T, then does that mean for an irreversible system -q(irreversible)/T? If so, why or why not. Don't really understand the logic behind this equation.

Thank you.
by Tara_Hekmati_3B
Tue Jan 17, 2017 4:09 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: units for enthalpy problems
Replies: 4
Views: 1021

Re: units for enthalpy problems

When finding standard rxn enthalpy it doesn't really matter if you use KJ/mol or just KJ (pretty sure my TA confirmed in class that both can be used and in the course reader it uses just KJ sometimes when finding the standard rxn enthalpy), but what you do have to make sure is labeled in KJ/mole is ...
by Tara_Hekmati_3B
Wed Jan 11, 2017 8:04 pm
Forum: Student Social/Study Group
Topic: Chemistry Joke
Replies: 28
Views: 6523

Re: Chemistry Joke

Exothermic reactions?
I studied them before they were cool. Pshht
by Tara_Hekmati_3B
Mon Nov 28, 2016 11:26 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Response of Equilibria to Change in CR pg. 138
Replies: 2
Views: 483

Re: Response of Equilibria to Change in CR pg. 138

If H2 is decreased then the equation shifts to the left in order to go back to equilibrium. This is because if the H2 concentration in the reaction decreases, then the product side of the equation (NH3) must begin to dissociate more readily in order to increase the concentration of the reactants and...
by Tara_Hekmati_3B
Mon Nov 21, 2016 6:00 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: pKa and pKb
Replies: 2
Views: 627

pKa and pKb

Are pKa and pKb measured on a scale of 0 to 14?

Also, does smaller pKb indicate a more basic base and the same for an acid with its pKa?

Thanks
by Tara_Hekmati_3B
Mon Nov 21, 2016 5:55 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: Why when given Ka = weak acid
Replies: 7
Views: 3888

Re: Why when given Ka = weak acid

We know this because if you had a strong acid, then the acid would dissociate completely in the reaction and there would be no more reactant left. Therefore, the dissociation constant (products/reactants) would have a zero in the denominator and is undefined. This shows why strong acids don't have a...
by Tara_Hekmati_3B
Wed Nov 16, 2016 6:13 pm
Forum: Naming
Topic: Alphabetizing Ligands
Replies: 4
Views: 926

Re: Alphabetizing Ligands

I understand this rule, but for ligands with names that don't match their formulas like ammine and ethylenediamine, do you put the coordination compound formula in alphabetical order based on the name of the ligand or it's formula?
by Tara_Hekmati_3B
Sat Nov 12, 2016 9:38 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Chem Equilibrium
Replies: 3
Views: 698

Chem Equilibrium

The Workbook practice quiz includes question that have not been covered in the first 4 pages of the equilibrium section of the Course Reader. Do we have to know these types of questions for quiz 3?

Lmk! Thanks!
by Tara_Hekmati_3B
Sat Nov 12, 2016 5:09 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: MO Diagram [ENDORSED]
Replies: 1
Views: 347

MO Diagram [ENDORSED]

Will we have to draw diagrams for compounds that go past Pi(2p)?
by Tara_Hekmati_3B
Sat Nov 12, 2016 5:02 pm
Forum: Naming
Topic: Polydentrites/Monodentrite [ENDORSED]
Replies: 1
Views: 458

Polydentrites/Monodentrite [ENDORSED]

What is the siginificance of something vein a Polydentrite as opposed to a Monodentrite?
by Tara_Hekmati_3B
Thu Nov 03, 2016 12:37 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 9651
Views: 3638687

Re: Post All Chemistry Jokes Here

Cation
Cat-i-on
noun, Chemistry
1. An ion with a paws-itive charge.
2. A very cute ion.
by Tara_Hekmati_3B
Wed Oct 26, 2016 12:20 pm
Forum: Lewis Structures
Topic: Hallogens
Replies: 1
Views: 508

Hallogens

Do hallogens normally stick to the octet guideline when they're surrounding the central and surrounding atom(s)? Or does that change when it's a central atom?
by Tara_Hekmati_3B
Thu Oct 20, 2016 9:23 pm
Forum: Ionic & Covalent Bonds
Topic: formal charge [ENDORSED]
Replies: 4
Views: 2156

formal charge [ENDORSED]

I understand the formal charge equation and how it's found for each atom, but what exactly is formal charge? And what is it used for?
by Tara_Hekmati_3B
Mon Oct 10, 2016 11:23 pm
Forum: Properties of Light
Topic: QUIZ 1 [ENDORSED]
Replies: 7
Views: 1694

QUIZ 1 [ENDORSED]

Do we have to know the polyatomic ions for the quiz this week? Also do we have to know how to name compounds?
by Tara_Hekmati_3B
Tue Oct 04, 2016 10:21 pm
Forum: DeBroglie Equation
Topic: Neutrons
Replies: 4
Views: 1023

Neutrons

Do neutrons act like electrons when they pass through a crystal? Meaning do they diffract and do they have wavelike properties?
by Tara_Hekmati_3B
Tue Sep 27, 2016 4:27 pm
Forum: Properties of Light
Topic: Photons
Replies: 4
Views: 888

Re: Photons

OK thanks, so there's no colorations between the photons and the frequency, right? because one looks at light on a smaller scale and the other is on a bigger scale.
by Tara_Hekmati_3B
Mon Sep 26, 2016 11:33 pm
Forum: Properties of Light
Topic: Photons
Replies: 4
Views: 888

Photons

So I understand that the intensity of energy is related to the number of photons present, but then why does the energy equation consider frequency (E=vh)?

Go to advanced search