Search found 51 matches
- Sun Mar 18, 2018 10:33 pm
- Forum: *Nucleophiles
- Topic: SN2 Reactions
- Replies: 4
- Views: 3573
Re: SN2 Reactions
How do we predict the product of a SN2 reaction?
- Sun Mar 18, 2018 10:34 am
- Forum: Balancing Redox Reactions
- Topic: test 2
- Replies: 5
- Views: 815
Re: test 2
How do you calculate it?
- Sun Mar 18, 2018 3:34 am
- Forum: Balancing Redox Reactions
- Topic: Winter 2011 Final Exam- Q3A
- Replies: 1
- Views: 432
Winter 2011 Final Exam- Q3A
Q3A. Balance the following redox equation which takes place under basic conditions.
MnO2(s) + ClO-(aq) -> MnO4^2-(aq)+Cl-(aq)
How do I do this?
MnO2(s) + ClO-(aq) -> MnO4^2-(aq)+Cl-(aq)
How do I do this?
- Sun Mar 11, 2018 11:56 pm
- Forum: Balancing Redox Reactions
- Topic: redox
- Replies: 6
- Views: 888
Re: redox
OIL RIG
Oxygen is losing - oxidizing agent gains electrons
Reduction is gaining - reducing agent loses electron
Oxygen is losing - oxidizing agent gains electrons
Reduction is gaining - reducing agent loses electron
- Sun Mar 11, 2018 11:55 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Chapters in Final Exam
- Replies: 3
- Views: 729
Chapters in Final Exam
In the syllabus it says that we're going to go over chapters 8, 9, 11, 14, and 15 throughout the quarter. Is the final going to include any other chapters or just these?
- Sun Mar 11, 2018 11:45 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: Molar Entropy
- Replies: 9
- Views: 1247
Re: Molar Entropy
Large = more complex = more possible orientations = higher entropy
Small = less complex = less possible orientations = lower entropy
Small = less complex = less possible orientations = lower entropy
- Sun Mar 04, 2018 11:24 pm
- Forum: General Rate Laws
- Topic: zero order in rate laws
- Replies: 8
- Views: 1030
Re: zero order in rate laws
You write it without it since it has no affect
- Sun Mar 04, 2018 10:58 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: k units [ENDORSED]
- Replies: 7
- Views: 1217
Re: k units [ENDORSED]
It’s different units depending on the rate order because each order has different powers the concentration is raised to so using the rate law you get different units for k in each rate order.
- Sun Mar 04, 2018 10:40 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Affects rate of chemical reactions
- Replies: 2
- Views: 441
Re: Affects rate of chemical reactions
Reactant concentrations, temperature, solvent and catalyst properties
- Sun Feb 25, 2018 11:57 pm
- Forum: General Rate Laws
- Topic: rate of reaction vs rate law
- Replies: 2
- Views: 429
Re: rate of reaction vs rate law
The rate law relates the rate of a reaction to the concentration or pressure of the reactants. The rate of a reaction is proportional to the concentration or pressure of the reactants modified by the reaction order.
- Sun Feb 25, 2018 11:50 pm
- Forum: First Order Reactions
- Topic: First order reactions vs second order reactions [ENDORSED]
- Replies: 3
- Views: 884
Re: First order reactions vs second order reactions [ENDORSED]
A first order reaction will have an overall order of one, the sum of all the exponents will be 1. A second order reaction will have an overall order of 2, the sum of all the exponents will be 2.
- Sun Feb 25, 2018 11:14 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: Homework 15.19
- Replies: 3
- Views: 518
Re: Homework 15.19
It's not always necessary, it's just better
- Sun Feb 18, 2018 11:15 pm
- Forum: Balancing Redox Reactions
- Topic: Basic and Acidic conditions [ENDORSED]
- Replies: 11
- Views: 6939
Re: Basic and Acidic conditions [ENDORSED]
Yes you’re right
- Sun Feb 18, 2018 11:05 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Electrochemical Series Definition
- Replies: 4
- Views: 759
Re: Electrochemical Series Definition
An electrochemical series is a series of chemical elements arranged in order of their standard electrode potentials. The series shows the order in which metals replace one another from their salts.
- Tue Feb 13, 2018 10:54 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Practice Midterm W18 by Lyndon and Michael (Q 1B)
- Replies: 2
- Views: 516
Practice Midterm W18 by Lyndon and Michael (Q 1B)
I'm not sure how to approach this problem or what formula to use. Can someone please explain how to do solve this. "Dr. Lavelle picks up the ice cream that he has just heated up (-2.8 degree C) and accidentally drops it on the ground and can’t eat it. Tears streaming down, he watches as half of...
- Sun Feb 11, 2018 11:58 pm
- Forum: Balancing Redox Reactions
- Topic: Oxidation
- Replies: 5
- Views: 823
Re: Oxidation
Yeah^^simply put, the oxidation number shows you the charge
- Sun Feb 11, 2018 11:55 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Entropy
- Replies: 6
- Views: 872
Re: Entropy
Vibration causes disorder which means an increase in entropy. Diatomic molecules would have greater entropy because the more complex the molecule the more entropy there is.
- Sun Feb 11, 2018 11:39 pm
- Forum: Entropy Changes Due to Changes in Volume and Temperature
- Topic: Cp v. Cv!
- Replies: 5
- Views: 809
Re: Cp v. Cv!
I kept wondering the same thing but during today's review session Lyndon said you'd use Cp when it specifically states "at constant pressure" in the problem.
- Sun Feb 04, 2018 11:57 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: Higher Molar Entropy
- Replies: 4
- Views: 835
Re: Higher Molar Entropy
Entropy values are given as standard molar entropy which is the entropy of one molecule of a substance as standard state conditions. The standard molar entropy of any substance increases as the temperature increases.
- Sun Feb 04, 2018 11:25 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Midterm
- Replies: 5
- Views: 724
Re: Midterm
I think my ta had said it's on chapters 8, 9, and 11
- Sun Feb 04, 2018 11:17 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Test 1 Question
- Replies: 4
- Views: 593
Test 1 Question
Why is "The contents of an ideal cooler at 3 degrees C" an isolated system and not closed?
- Sun Jan 28, 2018 11:58 pm
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Exothermic vs Exergonic and Endothermic vs Endergonic
- Replies: 3
- Views: 24860
Re: Exothermic vs Exergonic and Endothermic vs Endergonic
Exothermic/Endothermic: refer to transfer of heat or changes in enthalpy
Exergonic/Endergonic: refer to changes in free energy
Positive enthalpy change is endergonic because heat is absorbed and the products are higher in energy than the reactants
Exergonic/Endergonic: refer to changes in free energy
Positive enthalpy change is endergonic because heat is absorbed and the products are higher in energy than the reactants
- Sun Jan 28, 2018 11:52 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Microstates [ENDORSED]
- Replies: 3
- Views: 606
Re: Microstates [ENDORSED]
A microstate is a specific way that the energy of a system can be arranged. Microstates tend to be indistinguishable from each other which means the more indistinguishable the higher the entropy.
- Sun Jan 28, 2018 11:46 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Test question [ENDORSED]
- Replies: 16
- Views: 1705
Re: Test question [ENDORSED]
The question was pretty vague so I was also wondering how specific we were supposed to be because all I answered was that "Energy can't be created or destroyed, conservation of energy."
- Mon Jan 22, 2018 1:02 am
- Forum: Administrative Questions and Class Announcements
- Topic: Reversible and Isothermal Expansions
- Replies: 2
- Views: 415
Re: Reversible and Isothermal Expansions
Perfect- got it, thank you!
- Mon Jan 22, 2018 12:00 am
- Forum: Thermodynamic Systems (Open, Closed, Isolated)
- Topic: Entropy of an Isolated System
- Replies: 4
- Views: 829
Re: Entropy of an Isolated System
I think it doesn't decrease since it's at maximum entropy when it reaches equillibrium.
- Sun Jan 21, 2018 11:57 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Reversible and Isothermal Expansions
- Replies: 2
- Views: 415
Reversible and Isothermal Expansions
Just to clarify, for Chem 14b, will test 1 include Reversible and Isothermal Expansions?
- Sun Jan 21, 2018 11:52 pm
- Forum: General Science Questions
- Topic: Sig Figs
- Replies: 3
- Views: 765
Re: Sig Figs
Yes most likely; always pay attention to and use correct sig figs in chemistry.
- Sun Jan 14, 2018 11:58 pm
- Forum: Phase Changes & Related Calculations
- Topic: Endo and Exothermic Ways to Remember
- Replies: 28
- Views: 11430
Re: Endo and Exothermic Ways to Remember
Exothermic reminds me of exit and the first 2 letter in endothermic reminds me of in (enter).
- Sun Jan 14, 2018 11:52 pm
- Forum: Thermodynamic Definitions (isochoric/isometric, isothermal, isobaric)
- Topic: Thermochemical equation
- Replies: 5
- Views: 766
Re: Thermochemical equation
A thermochemical equation is a balanced chemical equation that has the physical states of all reactants and products along with the energy change. The reaction is endothermic if energy is a reactant and exothermic if energy is a product.
- Sun Jan 14, 2018 11:38 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Textbook Question
- Replies: 1
- Views: 232
Re: Textbook Question
Hi,
Dr. Lavelle noted in his syllabus "Please note we are not using the 7th edition. Students can use it but it is more expensive."
Dr. Lavelle noted in his syllabus "Please note we are not using the 7th edition. Students can use it but it is more expensive."
- Mon Jul 31, 2017 12:29 am
- Forum: Identifying Acidic & Basic Salts
- Topic: Salts
- Replies: 3
- Views: 894
Re: Salts
Chels Zh 1D wrote:Generally speaking, salts are the products of acids and bases, an ionic compound composing of cation and anion.
In addition to this, salts have an overall electrical charge of 0 therefore they are electrically neutral.
- Mon Jul 31, 2017 12:17 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Question about the exam
- Replies: 3
- Views: 639
Re: Question about the exam
My TA said the values will be given in the exam therefore we don't need to memorize them
- Mon Jul 31, 2017 12:14 am
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Chemical Equilibrium: Course Reader page 134
- Replies: 2
- Views: 584
Re: Chemical Equilibrium: Course Reader page 134
Species is referring to atoms, molecules, ions, elements, etc., being subjected to a chemical process
- Sun Jul 30, 2017 10:27 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Example from Pg 134 in Course Reader
- Replies: 1
- Views: 373
Example from Pg 134 in Course Reader
In the example from this page, K is being used to calculate the concentration of a species at equilibrium.
The example asks what PPCl3 is at equilibrium.
How do you go from KP = PPCl3 PCl2 / PPCl5 to PPCl3 = KP PPCl5 / PCl2 ?
The example asks what PPCl3 is at equilibrium.
How do you go from KP = PPCl3 PCl2 / PPCl5 to PPCl3 = KP PPCl5 / PCl2 ?
- Sun Jul 23, 2017 9:56 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: What is Kc and Q?
- Replies: 1
- Views: 424
Re: What is Kc and Q?
Kc is the ratio of products/reactants at equilibrium, Q is the direction a reaction will proceed.
- Sun Jul 23, 2017 9:37 pm
- Forum: Shape, Structure, Coordination Number, Ligands
- Topic: Self-Test 2 Problem 4
- Replies: 2
- Views: 575
Self-Test 2 Problem 4
The problem is:
For the complex ions listed below, determine the oxidation state and the coordination number of the central metal ion.
[Pt(CN)(NH3)3]^+
My question is, how do you find the oxidation state? Also, I got the coordination number 4, is that correct?
For the complex ions listed below, determine the oxidation state and the coordination number of the central metal ion.
[Pt(CN)(NH3)3]^+
My question is, how do you find the oxidation state? Also, I got the coordination number 4, is that correct?
- Sun Jul 23, 2017 9:20 pm
- Forum: Naming
- Topic: Naming Ligands
- Replies: 4
- Views: 752
Re: Naming Ligands
The method I used to practice naming ligands was I wrote the ligand on one side of a flashcard and the name of it on the back. I repeatedly went through the flashcards and looked at the name and named the ligand (checking the back to see if I was correct) or vice versa (looked at the ligand side of ...
- Sun Jul 23, 2017 8:59 pm
- Forum: Lewis Structures
- Topic: Homework problem 3.25
- Replies: 6
- Views: 1737
Re: Homework problem 3.25
For part b of problem 3.25, the answer is In2S3 but for In I got +3 and for S I got +6. How do you get In2S3? Same for part d; the answer is H2Te but for H I got +1 and for Te I got +6, the answer is H2Te not H6Te.
- Mon Jul 17, 2017 4:28 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Unpaired electrons
- Replies: 4
- Views: 773
Re: Unpaired electrons
In order to find the number of unpaired electrons you first have to write the electron configuration. Then, you can either draw the valence orbitals or picture it in your head and see how many electrons are unpaired. For example, if the electron configuration ends with 3p^4 you would have to know th...
- Mon Jul 17, 2017 4:12 am
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Question 2.41
- Replies: 1
- Views: 1140
Re: Question 2.41
(b) is not possible because l = 0 so ml must also = 0
(c) is not possible because the maximum value l can have is n - 1 and since n = 4, 4 - 1 = 3 so the maximum l can be is 3 not 4
(c) is not possible because the maximum value l can have is n - 1 and since n = 4, 4 - 1 = 3 so the maximum l can be is 3 not 4
- Mon Jul 17, 2017 3:46 am
- Forum: Dipole Moments
- Topic: Dipole moments
- Replies: 6
- Views: 1102
Re: Dipole moments
A dipole is a positive charge next to an equal but opposite negative charge. A dipole moment (μ) is the magnitude of the dipole.
- Wed Jul 12, 2017 7:21 am
- Forum: Wave Functions and s-, p-, d-, f- Orbitals
- Topic: Problem 2.47
- Replies: 3
- Views: 956
Problem 2.47
For each of the following ground-state atoms, predict the type of orbital (1s, 2p, 3d, 4f, etc.) from which an electron will be removed to form the +1 ion: (a) Ge; (b) Mn; (c) Ba; (d) Au.
The answers are: (a) 4p; (b) 4s; (c) 6s; (d) 6s
What method should I use to get the correct answers?
The answers are: (a) 4p; (b) 4s; (c) 6s; (d) 6s
What method should I use to get the correct answers?
- Mon Jul 10, 2017 12:02 am
- Forum: Ionic & Covalent Bonds
- Topic: Angstrom
- Replies: 1
- Views: 288
Angstrom
Do we have to know the Angstroms for chemical bonds or just that double bonds are shorter than single bonds and triple bonds are shorter than double bonds?
- Sun Jul 09, 2017 11:57 pm
- Forum: Ionic & Covalent Bonds
- Topic: Polyatomic Lewis Structures
- Replies: 5
- Views: 1402
Re: Polyatomic Lewis Structures
Anions gain electrons, cations lose electrons
- Sun Jul 09, 2017 11:44 pm
- Forum: Properties of Light
- Topic: Problem 1.57
- Replies: 1
- Views: 277
Problem 1.57
Problem 57 from Chapter 1 in the textbook:
Lines in the Balmer series of the hydrogen spectrum are observed at 656.3, 486.1, 434.0, and 410.2 m. What is the wavelength of the next line in the series?
How do you start off/solve this problem?
Lines in the Balmer series of the hydrogen spectrum are observed at 656.3, 486.1, 434.0, and 410.2 m. What is the wavelength of the next line in the series?
How do you start off/solve this problem?
- Sun Jul 09, 2017 11:33 pm
- Forum: Electron Configurations for Multi-Electron Atoms
- Topic: Electron Configuration Drawing
- Replies: 1
- Views: 377
Electron Configuration Drawing
Do we have to know how to draw electron configurations for the exam on Wednesday?
- Sun Jul 02, 2017 11:58 pm
- Forum: Properties of Light
- Topic: Light is a Wave, Light is Photons
- Replies: 3
- Views: 737
Re: Light is a Wave, Light is Photons
When light undergoes reflection, refraction, and diffraction it acts as a wave. When it packages its energy in small quanta it acts as a series of photons.
- Sun Jul 02, 2017 11:44 pm
- Forum: Photoelectric Effect
- Topic: Worked Example
- Replies: 1
- Views: 503
Worked Example
I'm going through the "The Quantum World" notes in the course reader and after reviewing the first worked example: "The following questions relate to the same metal used in a series of photoelectric experiments. If 3.61 x 10^-19 J is required to remove an electron with zero kinetic en...
- Sun Jul 02, 2017 11:28 pm
- Forum: Properties of Electrons
- Topic: Wave Properties of Electrons
- Replies: 3
- Views: 585
Re: Wave Properties of Electrons
A wave like property that electrons have is the discrete atomic energy levels. Another wave like property that electrons have is the diffraction of electrons from crystal planes in solid materials.
- Sun Jul 02, 2017 11:08 pm
- Forum: Properties of Light
- Topic: Light is a Wave, Light is Photons
- Replies: 3
- Views: 737
Re: Light is a Wave, Light is Photons
Light can't simultaneously be a pure wave and photon therefore there are not any instances where it acts as both.