Search found 30 matches
- Fri Mar 17, 2017 1:45 pm
- Forum: *Cyclohexanes (Chair, Boat, Geometric Isomers)
- Topic: Differentiation between drawn structures of chair conformation
- Replies: 1
- Views: 439
Re: Differentiation between drawn structures of chair conformation
I got my question answered. Yes, they are different drawings of the same structure so either is acceptable (in case anyone else wanted to know)
- Thu Mar 16, 2017 11:37 pm
- Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
- Topic: 2013 Final Q4 Part A
- Replies: 2
- Views: 570
Re: 2013 Final Q4 Part A
I am having the same problem :(
- Thu Mar 16, 2017 11:21 pm
- Forum: Balancing Redox Reactions
- Topic: Final 2013 Q3A
- Replies: 3
- Views: 878
Re: Final 2013 Q3A
I am confused on finding the Ecell value: they would have to give us each half-reaction cell potential but then how do we determine which is for the anode and which is for the cathode??
- Thu Mar 16, 2017 8:28 pm
- Forum: *Cyclohexanes (Chair, Boat, Geometric Isomers)
- Topic: Differentiation between drawn structures of chair conformation
- Replies: 1
- Views: 439
Differentiation between drawn structures of chair conformation
I am confused on the correct drawing of the chair conformation for cyclohexane. There is the way that shows two clear points (one up, one down) and the way that has 2 reflecting lines. For example, #15 in the Ch.3 homework draws it the second way. Would drawing the first way (a full shape) be marked...
- Mon Mar 06, 2017 10:32 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Quiz 3 Winter 2017
- Replies: 183
- Views: 29053
Re: Quiz 3 Winter 2017
Can someone help me with #3 I don't understand how both of them are nucleophiles? Are you referring to #6? Nucleophiles are species rich in electrons. For the benzene ring, this electron richness comes from its double bonds. For CH_{3}OCH_{3} the oxygen in the center of the compound can only be att...
- Sun Mar 05, 2017 7:19 pm
- Forum: First Order Reactions
- Topic: Determining Overall Reaction Rate
- Replies: 3
- Views: 765
Determining Overall Reaction Rate
When there are two of the same molecules as the reactants of a reaction, they are written [A][A], which equals [A]^2. This would make the reaction second-order. However, if there are 2 different molecules, the reaction would be [A]^1[B]^1. Does this make it an overall first-order reaction?
- Sun Mar 05, 2017 7:16 pm
- Forum: Reaction Mechanisms, Reaction Profiles
- Topic: Ch.15 Question 71
- Replies: 1
- Views: 397
Ch.15 Question 71
In this reaction mechanism, the answer key states that there are two intermediates and that the catalyst is OH-. But I remember learning that a catalyst is a molecule that is present in the beginning of the reaction and the end of the reaction (it is not used up). Based off of this knowledge, I wrot...
- Sun Feb 26, 2017 2:39 pm
- Forum: Administrative Questions and Class Announcements
- Topic: 2/24/17 Bruincast
- Replies: 19
- Views: 3349
Re: 2/24/17 Bruincast
Armani Dodson 1A wrote:Did you guys get any response ??? It still has the wrong lecture up.
I also emailed them and never got a response :(
- Mon Feb 20, 2017 11:50 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Quiz 2 Winter 2017
- Replies: 160
- Views: 24194
Re: Quiz 2 Winter 2017
Madeline Fox 2B wrote:Can someone explain why question 10 is false? I thought half-lives are always the same.
I am also confused by this question. I know that the equation is second-order, but do not understand why the decomposition would take different amounts of time.
- Mon Feb 20, 2017 6:58 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: 2017 Quiz 2
- Replies: 4
- Views: 859
Re: 2017 Quiz 2
Whoops! I meant Quiz 2 Preparation 2017. Question 5: "A reaction that has a very low activation energy ____" B) has a rate that does not change much with temperature
- Sun Feb 19, 2017 11:55 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: 2017 Quiz 2
- Replies: 4
- Views: 859
2017 Quiz 2
Can someone please explain why the answer to #5 is B) has a rate that does not change much with temperature? I am confused on this concept. Thanks!
- Sun Feb 12, 2017 9:41 pm
- Forum: Calculating Work of Expansion
- Topic: Practice Midterm Q3A Winter 2013
- Replies: 5
- Views: 854
Re: Practice Midterm Q3A Winter 2013
The answer is actually explained as q_katana= (1.45kg)(473 J/kg*K)(25.0˙C- 314.0˙C) and they didn't convert into Kelvin because they are looking for the difference and it would be the same answer if it is in celsius or kelvin, but I feel like it should be converted just to be able to cancel out wit...
- Sat Feb 11, 2017 7:47 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Clarifying what a voltaic cell is [ENDORSED]
- Replies: 1
- Views: 378
Clarifying what a voltaic cell is [ENDORSED]
I just want to get clarification on a voltaic cell: is it the method/diagram used in electrolysis? Where electrical energy is being converted to chemical energy? I am aware that a galvanic cell converts chemical energy into electrical energy, but the terminology of voltaic and electrolytic cell gets...
- Mon Jan 30, 2017 3:42 pm
- Forum: Administrative Questions and Class Announcements
- Topic: Quiz 1 Preparation Answers
- Replies: 130
- Views: 25205
Re: Quiz 1 Preparation Answers
Can someone verify that the equation needed to solve #12 is the one we learned for calculating standard free energy change? I am getting caught up in the wording: "Calculate the standard Gibbs free energy". Should I be using a different equation (even though we're given standard change in...
- Mon Jan 30, 2017 12:53 am
- Forum: Administrative Questions and Class Announcements
- Topic: Quiz 1 Preparation Answers
- Replies: 130
- Views: 25205
Re: Quiz 1 Preparation Answers
Can someone verify that the equation needed to solve #12 is the one we learned for calculating standard free energy change? I am getting caught up in the wording: "Calculate the standard Gibbs free energy". Should I be using a different equation (even though we're given standard change in ...
- Sat Jan 28, 2017 4:16 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Clarification on heat transfer but no temp change
- Replies: 2
- Views: 457
Re: Clarification on heat transfer but no temp change
Thanks! That actually really helped.
- Fri Jan 27, 2017 2:44 pm
- Forum: Concepts & Calculations Using First Law of Thermodynamics
- Topic: Clarification on heat transfer but no temp change
- Replies: 2
- Views: 457
Clarification on heat transfer but no temp change
I am conceptually confused on how heat (a form of energy) can be transferred into or out of a system, yet there is no temperature change of that system. I do understand that temperature is the measure of thermal motion, not heat, but still need someone to clarify. Thanks!
- Fri Jan 20, 2017 5:02 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Help With Question 8.39 [ENDORSED]
- Replies: 2
- Views: 583
Re: Help With Question 8.39 [ENDORSED]
Ok, thanks so much.
I was confused because in my discussion my TA gave us a different value for enthalpy of fusion that we used in an example for water. It was 334 J/mol.
I was confused because in my discussion my TA gave us a different value for enthalpy of fusion that we used in an example for water. It was 334 J/mol.
- Thu Jan 19, 2017 10:12 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Help With Question 8.39 [ENDORSED]
- Replies: 2
- Views: 583
Help With Question 8.39 [ENDORSED]
What is the value 6.01 kJ.mol^-1 representing in this answer? It has the same units as Gibbs free energy, but when I looked in the index that value for H20 was way different. Shouldn't it be the heat constant for that molecule? And where can we find that value in the textbook?
Thanks!
Thanks!
- Tue Jan 17, 2017 11:32 pm
- Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
- Topic: Reaction Enthalpies: When kJ and when kJ/mol?
- Replies: 1
- Views: 467
Re: Reaction Enthalpies: When kJ and when kJ/mol?
If you get the answer in kJ/mol then it is in standard heat capacity, which assumes it is per mole. If it is in kJ, then it is not in standard form and has been adjusted for the fact that the amount of the substance in question is greater or less than one mole. This would entail finding the moles of...
- Mon Jan 16, 2017 11:07 pm
- Forum: Administrative Questions and Class Announcements
- Topic: CH 8 Which HW Problems to do first?
- Replies: 14
- Views: 10450
Re: CH 8 Which HW Problems to do first?
In regards to the Ch.8 questions, is there any way to choose which of the questions to complete if time is an issue and completing all of the problems will be near impossible while also keeping up with the course (in order to maximize studying and time efficiency)?
- Fri Nov 27, 2015 2:08 pm
- Forum: Lewis Structures
- Topic: The "Lewisiana" Purchase Video
- Replies: 4
- Views: 986
Re: The "Lewisiana" Purchase Video
Of course, I was thinking that wasn't right when we were filming! Sorry for the mistake.
- Wed Nov 18, 2015 2:41 pm
- Forum: Lewis Structures
- Topic: The "Lewisiana" Purchase Video
- Replies: 4
- Views: 986
The "Lewisiana" Purchase Video
This video covers the process of how to determine Lewis structures for both ionic and covalent bonds. It also explains the exceptions of the process, resonance, and formal charge.
- Wed Nov 04, 2015 11:39 am
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: Determine where sigma and pi bonds go in diagram
- Replies: 2
- Views: 422
Determine where sigma and pi bonds go in diagram
If you have an atom that has less than 8 protons and an atom with more than 8, how do you determine where the sigma and pi bonds go in the diagram? Which one trumps the other?
- Wed Oct 28, 2015 11:28 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Ch.3 #95
- Replies: 1
- Views: 479
Ch.3 #95
The compound given is C(H2)3 with charge of 2-. Do we only draw bonds for connecting the 3 CH2 compounds to the central carbon? I first bonds for all of the atoms, but the solutions manual showed to do otherwise. Is that because molecular shape/resonance only depends on the central atom? If so, what...
- Sat Oct 24, 2015 9:32 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Bond Angle of Seesaw shape
- Replies: 1
- Views: 1451
Bond Angle of Seesaw shape
What are the bond angles for seesaw shape? Are they the same trigonal bipyramidal?
- Fri Oct 23, 2015 12:37 am
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Determining atom to double bond with in Lewis Structure
- Replies: 1
- Views: 372
Determining atom to double bond with in Lewis Structure
How do you determine which atom of a compound to create a double bond? Is it the most electronegative atom?
- Thu Oct 15, 2015 1:23 pm
- Forum: Empirical & Molecular Formulas
- Topic: Calculating molecular formula
- Replies: 1
- Views: 385
Calculating molecular formula
One of the quiz questions in the workbook asks to find the molecular formula of a given mass composition. It also provides the total molar mass. After many tries, I continue to get a start mole amount for one of the elements. Should I assume I am doing something wrong if one of the values is a decim...
- Thu Oct 08, 2015 1:02 pm
- Forum: Properties of Light
- Topic: Importance of light waves versus quantized photons
- Replies: 2
- Views: 460
Re: Importance of light waves versus quantized photons
Okay. But why not just change the type of light (i.e., blue to purple light for a higher frequency and therefore more energy) instead of using photons?
Again, I am just curious despite knowing that photons are the way to go when solving these types of problems.
Again, I am just curious despite knowing that photons are the way to go when solving these types of problems.
- Fri Oct 02, 2015 2:20 pm
- Forum: Properties of Light
- Topic: Importance of light waves versus quantized photons
- Replies: 2
- Views: 460
Importance of light waves versus quantized photons
Why is increasing the energy of light waves not enough to determine the emission of the electron from the metal in photoelectric effect?