## Search found 44 matches

Sat Mar 12, 2016 9:22 pm
Forum: *Alkenes
Topic: Various naming for Vinyl and Allyl
Replies: 1
Views: 405

### Various naming for Vinyl and Allyl

Can a vinyl substituent group also be called an eth-1-enyl? Can an allyl be called a prop-1-enyl? Thank you so much!
Sat Mar 12, 2016 9:20 pm
Forum: *Alkenes
Topic: question 5 final 2013
Replies: 1
Views: 436

### Re: question 5 final 2013

Alkenes can be pseudo-functional groups when they're attached to a main carbon chain. In this particular problem, there is an alkene hanging off of the main chain, so it is technically a functional group. However, when alkenes are in the main chain, they are not functional groups.
Sat Mar 12, 2016 8:03 pm
Forum: Phase Changes & Related Calculations
Topic: 2006 Final Q1a.
Replies: 1
Views: 360

### Re: 2006 Final Q1a.

In order to explain this, you need to start to calculate the heat needed to heat the ice to water at 5°. In doing that, you need to do two things: 1. heat to melt, using the equation q=n*deltaHfusion, 2. Heating from 0° to 5°, using q=mcdeltaT. You need to solve for deltaH, so just leave that be for...
Fri Mar 11, 2016 3:08 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Winter Final 2013 4B
Replies: 1
Views: 316

### Re: Winter Final 2013 4B

1. After you figure out that Q=1/[O2], you need to essentially figure out what [O2] is. This makes sense, since you calculated Q in part A, and [O2] is your unknown. 2. With some logic, you can devise that [O2]= your initial [O2], or [O2]initial + change in concentration, or delta [O2]. This is wher...
Fri Mar 11, 2016 2:46 pm
Forum: *Cyclohexanes (Chair, Boat, Geometric Isomers)
Topic: Drawing Hydrogens in Conformations
Replies: 1
Views: 334

### Re: Drawing Hydrogens in Conformations

Generally, you don't need to draw every hydrogen. I was talking to a TA, and she said that it was best if you had the larger substituent in an equatorial up position, for example, to also draw the corresponding hydrogen in the axial down position, just to show that you understand the conformation. H...
Wed Mar 09, 2016 10:19 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Winter 2015 Final #1B
Replies: 1
Views: 292

### Winter 2015 Final #1B

Question #1B on the Winter 2015 Final Exam, on page 227 of the course reader asks, "The heat reveals inscriptions on the ring, confirming that it is indeed the One Ring. Frodo decides to destroy it by melting it. Heating the ring from 25°C to its melting point requires 13.4 KJ of heat. What is ...
Tue Mar 08, 2016 12:28 am
Forum: *Alkanes and Substituted Alkanes (Staggered, Eclipsed, Gauche, Anti, Newman Projections)
Topic: Winter 2011 Final #8D
Replies: 3
Views: 502

### Winter 2011 Final #8D

On page 184 of the course reader, Question 8D asks, "Viewing along the C3-C4 bond of 1-chloro-5-fluorohexane, draw a Newman projection of the most stable conformation. Since this is a cyclohexane, the most stable conformation would be a chair conformation, with chloro (the larger substituent) i...
Tue Mar 01, 2016 10:23 pm
Forum: *Constitutional and Geometric Isomers (cis, Z and trans, E)
Topic: Z and E
Replies: 1
Views: 309

### Z and E

Is it acceptable to refer to a cis isomer as a Z isomer, and to a trans isomer as an E isomer? I know that it does not work vice versa.
Sun Feb 28, 2016 11:18 pm
Forum: *Alkanes
Topic: Quiz 3 Preparation Page 43, Question 4
Replies: 3
Views: 404

### Quiz 3 Preparation Page 43, Question 4

Question 4 on page 43 of the workbook states, "Draw a line structure of 7-fluoro-3-methyl-4-vinyl-nonane." Do we need to know what the vinyl substituent means for quiz 3 and/or the final?
Wed Feb 24, 2016 2:31 pm
Forum: *Alkynes
Topic: Molecules with both triple and double bonds
Replies: 1
Views: 297

### Molecules with both triple and double bonds

If a molecule has both double and triple bonded carbons, is it considered an alkene or alkyne?
Sun Feb 21, 2016 6:57 pm
Forum: *Organic Reaction Mechanisms in General
Topic: Alkyl and Aryl Cations
Replies: 2
Views: 460

### Re: Alkyl and Aryl Cations

Thank you so much!
Sat Feb 20, 2016 5:59 pm
Forum: *Organic Reaction Mechanisms in General
Topic: Alkyl and Aryl Cations
Replies: 2
Views: 460

### Alkyl and Aryl Cations

Just for clarification, what is the difference between a alkyl and aryl cation? Thanks so much!
Sat Feb 20, 2016 5:56 pm
Forum: *Nucleophiles
Topic: Organolithium and Grignard Reatants
Replies: 2
Views: 981

### Organolithium and Grignard Reatants

As stated on page 146 of the organic handbook, "two well known organometallic compounds that generate very strong nucleophiles (carbanions) are organolithium and Grignard Reactants." What exactly is the difference between these two? And how are they significant? I keep reading the page ove...
Tue Feb 16, 2016 11:48 pm
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Quiz 2 Preparation W14: Q7
Replies: 3
Views: 538

### Re: Quiz 2 Preparation W14: Q7

You cancelled out your intermediates correctly. Now, when you write the rate law, since the slow step is the rate determining step, you only include the reactants in the slow step. In this case, only the NOs are involved in the slow step. Therefore, you can assume that the order with respect to O2 i...
Tue Feb 16, 2016 11:45 am
Forum: Kinetics vs. Thermodynamics Controlling a Reaction
Topic: Kinetic Control
Replies: 2
Views: 549

### Kinetic Control

In the book and in some of the past midterms, there has been some mention of "kinetic control" or "kinetically controlled reactions." How does this concept work?
Mon Feb 15, 2016 8:57 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: Activation Energy and Temperature
Replies: 1
Views: 417

### Activation Energy and Temperature

Is there an inverse relationship between activation energy and temperature? If so, how can you explain such a relationship?
Tue Feb 09, 2016 6:41 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Midterm 2014 Question 8
Replies: 1
Views: 355

### Re: Midterm 2014 Question 8

Potential difference can be negative, given that this reaction doesn't necessarily need to be spontaneous. Ka is the equilibrium constant expression with respect to HF, which would be given by Ka=[H+][F-]/[HF]. In order to get the Ka of HF, H+ and F- need to be in the reactants, so yes, you would fl...
Tue Feb 09, 2016 11:29 am
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Is E a state function?
Replies: 2
Views: 484

### Re: Is E a state function?

viewtopic.php?f=140&t=3754

viewtopic.php?f=141&t=3890

Sorry the last post didn't post as links!
Tue Feb 09, 2016 11:27 am
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Is E a state function?
Replies: 2
Views: 484

### Re: Is E a state function?

Here are some links to explain why:

viewtopic.php?f=140&t=3754

viewtopic.php?f=141&t=3890

Hope this helped!
Tue Feb 09, 2016 12:50 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Galvanic Cells and Midterm Questions
Replies: 2
Views: 487

### Re: Galvanic Cells and Midterm Questions

On Question 7 on Midterm 2015, it switches up the normal orientation of the anode and the cathode, placing the cathode on the left and the anode on the right. Should the electrodes be labelled in this case? Or would there at least be the oxidation half-reaction given at the anode, or the reduction h...
Tue Feb 09, 2016 12:47 am
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Midterm 2012 Question 8
Replies: 3
Views: 444

### Re: Midterm 2012 Question 8

Using either equation should yield the correct answer, given if you use ln, your equation is Ecell= E0cell-(RT/nF)lnQ, and if you use log, your equation is Ecell=E0cell-(0.05916V/n)logQ. I tend to use the first equation; for some reason it always leads me to the right answer. And in this case, would...
Tue Feb 09, 2016 12:09 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Galvanic Cells and Midterm Questions
Replies: 2
Views: 487

### Galvanic Cells and Midterm Questions

Given a diagram of a galvanic cell on the midterm, will the cathode and anode be labelled in all problems? Or will each electrode have a labelled half reaction, especially in electrolysis problems? I just want to be sure.
Sat Feb 06, 2016 4:10 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Winter 2013 Midterm #3
Replies: 2
Views: 357

### Winter 2013 Midterm #3

The second party of Question #3 on the Winter 2013 Midterm asks to calculate the work done by the steam. 1. Can you assume that the work is zero, since there is no volume change indicated? 2. If you were to use the equation w=-PdeltaV, and substitute values to get w=-delta (nRT), why does the answer...
Sun Jan 31, 2016 8:59 pm
Forum: Balancing Redox Reactions
Topic: Balancing #14.5 D
Replies: 1
Views: 362

### Re: Balancing #14.5 D

I think I answered my own question. To balance this reaction, I added 8H2O molecules to the left side to balance out the Os on both sides. Then, I added 4H2Os to the right side to balance the Hs. By convention, I added 8 OH- molecules to the left, and then multiplied the 4H2O molecules on the right ...
Sun Jan 31, 2016 8:53 pm
Forum: Balancing Redox Reactions
Topic: Balancing #14.5 D
Replies: 1
Views: 362

### Balancing #14.5 D

On page 604, #14.5 D asks to balance the reaction P4(s) -> H2PO2(-1)(aq) + PH3 (g) in a basic solution. The solutions manual, on page 378, shows the oxidation half reaction, but does not include any water in that equation. I thought water was needed to balance the oxygen in the reaction? Does it som...
Thu Jan 28, 2016 11:23 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Calculating Potential Difference as a State Function
Replies: 1
Views: 326

### Calculating Potential Difference as a State Function

Page 49 in the course reader shows that E(standard) equals the summation of E(standard) of the cathode -summation of E(standard) of the anode. Given that information, can one assume that E(standard) is a state function?
Mon Jan 25, 2016 7:20 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Question #11 on Practice Quiz 1 2015
Replies: 3
Views: 471

### Question #11 on Practice Quiz 1 2015

Question #11 reads, "How many grams of water can be heated from 25.0 degrees Celsius to 100.0 degrees Celsius by the heat released from converting 49.7g PbO to Pb?" Can you assume that all of the heat lost from the PbO system is lost to the water surroundings? And how do you calculate the ...
Mon Jan 25, 2016 7:12 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Quiz 1 Preparation #9b Error?
Replies: 1
Views: 355

### Re: Quiz 1 Preparation #9b Error?

When you calculate the delta G for this equation, delta H is given in units of joules per mole, and delta S in units of joules per mole x Kelvin. When you multiply delta S by temperature, that leaves the overall delta G calculation in joules per mole. Usually, delta G is measured in kilojoules per m...
Mon Jan 25, 2016 6:50 pm
Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
Topic: Question #9 in Quiz 1 Winter 2015
Replies: 4
Views: 813

### Question #9 in Quiz 1 Winter 2015

Question #9, on page 18 in the workbook reads, "A sample of 1 mole of gas initially at 1 atm and 298 K is heated at constant pressure to 350 K, then the gas is compressed isothermally to its initial volume and finally it is cooled to 298K at constant volume. Which of the following values is zer...
Tue Jan 19, 2016 4:22 pm
Forum: Phase Changes & Related Calculations
Topic: Specific Heat Capacity in Different Phases
Replies: 1
Views: 683

### Specific Heat Capacity in Different Phases

In Quiz 1 Preparation in the workbook, Winter 2014 #1 shows a heating curve. The heating curve, by nature of the graph, shows us that the specific heat capacity of this particular substance is greater in its solid state than liquid, and greater in liquid than in gas. Is this true for all substances?...
Tue Jan 12, 2016 4:37 pm
Forum: Calculating Work of Expansion
Topic: Irreversible expansion vs Reversible Expansion
Replies: 1
Views: 241

### Irreversible expansion vs Reversible Expansion

In problem 8.11, you are asked to compare the amount of work of two processes. The first, as stated by the solutions manual, uses irreversible expansion and the second uses reversible expansion. How do you know when to use one versus the other?
Sun Jan 10, 2016 7:18 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Molar Heat Capacity vs Specific Heat Capacity
Replies: 1
Views: 382

### Molar Heat Capacity vs Specific Heat Capacity

When should one use molar heat capacity, as opposed to specific heat capacity in a thermochemical calculation?
Fri Dec 04, 2015 8:39 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: 2012 Final Problem #8
Replies: 1
Views: 323

### 2012 Final Problem #8

On the 2012 Final problem on page 247, in order to solve for the pH of the solution, one must solve for the final concentration of Hydrogen. It is found to be essentially 4.0x10^-5. To find the pH, you would take the -log(4.0x10^-5). The course reader lists the answer as 4.30, but -log(4.0x10^-5) is...
Thu Dec 03, 2015 9:15 am
Forum: General Science Questions
Topic: Fall 2010 Final Exam Question 5
Replies: 1
Views: 634

### Fall 2010 Final Exam Question 5

On page 223 of the course reader, the question reads "Draw the most stable Lewis Structure for the following Bronsted acids and list them from least acidic to most acidic: HClO3;HCLO; HCLO2;HCLO4. Explain their trend in increasing stability. Why is HClO4 the most acidic?
Sun Nov 29, 2015 11:03 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Temperature and LeChatelier's Principle
Replies: 2
Views: 410

### Temperature and LeChatelier's Principle

What impact does a change in temperature have in the way a reaction proceeds?
Thu Nov 19, 2015 5:24 pm
Forum: Bronsted Acids & Bases
Topic: Amphiprotic Acids & Bases
Replies: 1
Views: 3716

### Amphiprotic Acids & Bases

On Page 137 of the course reader, it states, "water can act as a proton donor and as a proton acceptor, and is therefore amphiprotic." Are there any other molecules in existence that can also be amphiprotic?
Mon Nov 09, 2015 9:22 am
Forum: Naming
Topic: Chelating Ligands
Replies: 1
Views: 265

### Chelating Ligands

Page 104 of the course reader explains that, "Chelating ligands bind cations tightly: EDTA4- ion used to remove metals from solution." What is a chelating ligand and what is its significance?
Wed Oct 28, 2015 10:20 am
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: N2+
Replies: 2
Views: 1265

### N2+

On the quiz 2 preparation, on page 43 in the workbook, problem #5 asks to "Write out the electron configuration for N2+." When filling out the 2p sigma and 2p pi orbitals, will the electrons fill the sigma shell before moving to the pi orbitals? Or do they fill out all 3 orbitals?
Mon Oct 26, 2015 10:28 am
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Replies: 1
Views: 254

What is the difference between a radical and a biradical? And what is the significance of each?
Fri Oct 23, 2015 10:21 am
Forum: Hybridization
Topic: Textbook Problem 3.21C
Replies: 1
Views: 876

### Textbook Problem 3.21C

Problem #21 reads, "Give the ground state electron configuration and number of unpaired electrons expected for each of the following ions: c)Te2-. The solution manual says the answer is [Xe] with no unpaired electrons. I'm not exactly sure how this is the answer? I thought Te2- still had unpair...
Wed Oct 14, 2015 11:32 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Atomic Spin Number
Replies: 2
Views: 415

### Atomic Spin Number

If a question was to ask to find the four magnetic quantum numbers for Carbon, for example, would it matter whether I answered +1/2 or -1/2 for the magnetic spin number?
Sun Oct 11, 2015 6:08 pm
Forum: DeBroglie Equation
Topic: Significant Figures and the de Broglie Wavelength Equation
Replies: 1
Views: 476

### Significant Figures and the de Broglie Wavelength Equation

On Page 25 of the workbook, practice problem #9 asks, "Calculate the de Broglie wavelength of a 0.155kg ball traveling at 85.0m/s." When using the equation, the answer comes out to 5.03x10^-35m. However, on page 26, the answer for problem #9 lists "5x10^-35m." Is there a particul...
Fri Oct 02, 2015 12:43 pm
Forum: DeBroglie Equation
Topic: Measurable De Broglie Wavelength
Replies: 2
Views: 543

### Measurable De Broglie Wavelength

On page 49 in the course reader, there is a worked example regarding De Broglie wavelength. It reads, "If you are driving a 1.50x10^3 kg car at 27.0m/s, what is the De Broglie wavelength of your car? Does it have any measurable wavelike properties?" Using the equation, it is found that the...
Fri Oct 02, 2015 12:43 pm
Forum: DeBroglie Equation
Topic: Measurable De Broglie Wavelength
Replies: 1
Views: 361

### Measurable De Broglie Wavelength

On page 49 in the course reader, there is a worked example regarding De Broglie wavelength. It reads, "If you are driving a 1.50x10^3 kg car at 27.0m/s, what is the De Broglie wavelength of your car? Does it have any measurable wavelike properties?" Using the equation, it is found that the...