Search found 17 matches

Sun Mar 01, 2015 9:02 am
Forum: General Rate Laws
Topic: Writing rate law: the 2 questions
Replies: 5
Views: 867

Re: Writing rate law: the 2 questions

Wow, i finally understand it. Thank you for clarifying it.
Mon Feb 16, 2015 6:09 pm
Forum: General Rate Laws
Topic: Writing rate law: the 2 questions
Replies: 5
Views: 867

Writing rate law: the 2 questions

Hey, I have 2 questions about writing the rate law: 1. I noticed that the examples used in lecture were with reactants that had 1 as its stoichiometric coefficient. How do you write the rate law when a reactant has 2 (or a number other than 1) as a coefficient? Example: 2A + B --> 2C 2. My second qu...
Mon Jan 26, 2015 3:23 pm
Forum: Concepts & Calculations Using First Law of Thermodynamics
Topic: Quiz 1 prep #1 Winter 2014 Question #11
Replies: 2
Views: 452

Re: Quiz 1 prep #1 Winter 2014 Question #11

Hi!! \Delta U = + because the question says " as it returns to the original internal energy". Its internal energy is increasing at it is returning to its original internal energy calculated in part 1. The key word in the question is returns which insinuates that some form of energy, is cau...
Sat Nov 22, 2014 9:14 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: ICE box
Replies: 2
Views: 427

Re: ICE box

1 mole N 2 + 3 mole H 2 \rightleftharpoons 2 moles of NH 3 Notices: 1-- For every 2 moles of NH 3 produced, N 2 was fully used up (1 mole) BUT the reaction reached equilibrium when only 0.150 moles of NH 3 was produced . This means that N 2 has not fully reacted. Note: You can make these data propor...
Wed Nov 19, 2014 11:27 am
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Understanding Reaction quotient (Q)
Replies: 1
Views: 300

Understanding Reaction quotient (Q)

Reaction quotient (Q ) is taken at any time during the reaction which can be before or after equilibrium is reached. . With this concept in mind: Q < K means the ratio [P]/[R] was taken before equilibrium was reached ; The reactant is still forming products ( R --> P ) so product/forward reaction i...
Sat Nov 01, 2014 12:27 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: SOCl2 Expected Bond Length
Replies: 1
Views: 601

Re: SOCl2 Expected Bond Length

1) OSCI is a radical with an unpaired lone pair (has a total of 19 e - ). As a radical, it wants a paired electron and is treated as an anion when writing the VSPER notation;Thus, it is written as AX 2 E 2 although it technically has 1 paired electron and 1 unpaired electron 2) ClSCl has a bent mole...
Sat Nov 01, 2014 12:05 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Ch. 3 #7 Question on number of electrons
Replies: 3
Views: 1127

Re: Ch. 3 #7 Question on number of electrons

ICl 2 is a radical because it as 1 unpaired electron. For this reason, it is most likely going to form an anion making it ICl 2 - because it really wants to have a paired electron . Note: The unpaired electron is willing to react with other unpaired electrons. Thus, the book assumes that it is in an...
Wed Oct 22, 2014 9:11 am
Forum: Photoelectric Effect
Topic: Hw 1.23
Replies: 3
Views: 1013

Re: Hw 1.23

To add to what Justin Said, the key part of the question is "wavelength of the ejected electron ". Kinetic energy is the excess energy which the electron emits. Also, the velocity given is the "velocity of the electron that is emitted" and NOT the velocity at which the emitted el...
Wed Oct 22, 2014 9:02 am
Forum: Photoelectric Effect
Topic: Work Function
Replies: 1
Views: 349

Re: Work Function

Work function is the energy required to remove one electron (an atom) from the metal surface. Unit is just Joules which implicitly implies per atom
P.S: energy is always in Joules
Fri Mar 14, 2014 3:42 pm
Forum: General Rate Laws
Topic: Finding the order of each reactant
Replies: 1
Views: 315

Finding the order of each reactant

For order questions similar to this: What is the order for each reactant? EXPERIMENT [A] o [B] o [C] o INITIAL RATE 1 10 100 700 2 2 20 100 300 4 3 20 200 200 16 4 10 100 400 2 Is it accepted if we find the order conceptually (like below) , or is the grading solely based on mathematical work. Compar...
Mon Mar 03, 2014 10:06 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: Kinetic/Thermodynamic Stability vs. Control
Replies: 3
Views: 649

Re: Kinetic/Thermodynamic Stability vs. Control

Page 163 of the introduction to organic chemistry book clarifies what is means to the kinetically stable and kinetically controlled. But yes both mean the same thing. Recall: Kinetically stability deals with the rate of the reaction. A slow reaction [delta G < 0 , Large activation energy (Ea)] is k...
Mon Feb 24, 2014 11:24 pm
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: Kinetic Control
Replies: 3
Views: 540

Re: Kinetic Control

Thanks ^_^, That made so much sense!! I get it now
Mon Feb 24, 2014 11:23 pm
Forum: General Rate Laws
Topic: Writing the rate law
Replies: 3
Views: 452

Re: Writing the rate law

So we have to solve for the coefficient even if there's coefficient infront? To clarify, the coefficient is used only in the unique rate of reaction -1/a d[A]/dt... and nothing else?
Mon Feb 24, 2014 10:54 pm
Forum: General Rate Laws
Topic: Order reactions
Replies: 2
Views: 427

Re: Order reactions

To add on to ch1995's response, the coefficients of the concentrations when you write the rate law is the order of that molecule.
For example: In Rate= k [O2][NO]2 , the order of O2 is 1 and the order of NO is 2. Therefore, the overall order is 1+2 =3
Mon Feb 24, 2014 10:39 pm
Forum: General Rate Laws
Topic: Writing the rate law
Replies: 3
Views: 452

Writing the rate law

In number 4 of the workbook, the reaction N2O --> N2 + O2 and the rate k[N2O] are given. Just to clarify, the rate law is written for a balanced equation(reaction), right ?
Mon Feb 24, 2014 11:33 am
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: Kinetic Control
Replies: 3
Views: 540

Kinetic Control

What does it mean for a reaction to be under Kinetic control? Is Kinetic control similar to thermodynamic control?
Sun Nov 24, 2013 8:14 pm
Forum: Empirical & Molecular Formulas
Topic: Empirical and Molecular Formulas Pre-Module Assessment Fall
Replies: 1
Views: 422

Empirical and Molecular Formulas Pre-Module Assessment Fall

For question 2 (listed below), when finding the moles of fluorine gas, why isn't the molar mass of fluorine gas (F2) 38 g/mol instead of 19 g/mol? 339.20 g of a cobalt metal is reacted with fluorine gas to produce a compound with a molar mass of 996.08 g/mol. What is the empirical formula of the ne...