Search found 24 matches
- Tue Mar 08, 2016 9:54 pm
- Forum: *Cyclohexanes (Chair, Boat, Geometric Isomers)
- Topic: cis conformation
- Replies: 2
- Views: 601
Re: cis conformation
I believe trans would be one substituent on axial and the other on equatorial. As for cis, the more stable confirmation would be if the larger substituents were both on the equatorial axis.
- Mon Feb 29, 2016 5:38 pm
- Forum: *Constitutional and Geometric Isomers (cis, Z and trans, E)
- Topic: Dashes in Naming
- Replies: 1
- Views: 467
Dashes in Naming
For the last example on page 106 of the course reader, why are there dashes in between bromo-chloro-propene? Why isn't the answer just E-1,1-bromochloropropene? I thought dashes are only used when switching between numbers and letters.
Thank you!
Thank you!
- Fri Feb 26, 2016 8:48 am
- Forum: *Identifying Primary, Secondary, Tertiary, Quaternary Carbons, Hydrogens, Nitrogens
- Topic: Equivalent H
- Replies: 2
- Views: 769
Re: Equivalent H
Also, in the example above the carbons can be considered equivalent as well.
- Thu Feb 18, 2016 12:28 am
- Forum: First Order Reactions
- Topic: Rate Law Units
- Replies: 1
- Views: 560
Rate Law Units
For first-order rate law constants, does the units need to be in s-1 or min-1?
The solutions guide for 15.29 part a lists the rate constant as 0.17min instead of in seconds.
Thank you!
The solutions guide for 15.29 part a lists the rate constant as 0.17min instead of in seconds.
Thank you!
- Wed Feb 17, 2016 10:55 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Chapter 15 question 3c.
- Replies: 2
- Views: 830
Re: Chapter 15 question 3c.
Basically, just divide the rate you got in part a by 2, because there are 2 moles of NO2 in the balanced equation.
6.5 x 10^-3M/s / 2 = 3.3 x 10^-3 M/s
6.5 x 10^-3M/s / 2 = 3.3 x 10^-3 M/s
- Mon Feb 15, 2016 5:51 pm
- Forum: Kinetics vs. Thermodynamics Controlling a Reaction
- Topic: Forward Reaction
- Replies: 3
- Views: 745
Re: Forward Reaction
In addition, we can use some sort of mechanism to remove the product, so that we do not have to take the reverse reaction into consideration. Or, the product may be a gas, in which case the reverse reaction will not occur.
- Mon Feb 15, 2016 5:50 pm
- Forum: Method of Initial Rates (To Determine n and k)
- Topic: Calculating n and k from more than 3 reactions
- Replies: 1
- Views: 497
Re: Calculating n and k from more than 3 reactions
Even if you are provided more than three reactions, you wouldn't require more than three to find k or n.
- Sun Feb 07, 2016 6:41 pm
- Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
- Topic: Calculate Standard Potential from Half Reaction
- Replies: 1
- Views: 1034
Calculate Standard Potential from Half Reaction
For HW 14.27, why is it that we need to convert the E0 values into deltaG0 values? Why isn't the answer simply -1.79V + (-0.61V)? Question: 14.27 Using data in Appendix 2B, calculate the standard potential for the half-reaction U4+(aq) + 4e- --> U(s). The half reactions I used are U3+ + 3e- --> U E0...
- Thu Feb 04, 2016 4:59 pm
- Forum: Interesting Applications: Rechargeable Batteries (Cell Phones, Notebooks, Cars), Fuel Cells (Space Shuttle), Photovoltaic Cells (Solar Panels), Electrolysis, Rust
- Topic: Electrolytic vs. Galvanic Cells
- Replies: 1
- Views: 597
Re: Electrolytic vs. Galvanic Cells
Galvanic cells release energy, so they are exothermic. Gibbs free energy is negative, so the reaction is spontaneous. The cell potential difference is positive. E0 is positive. Electrolytic cells require energy, so they are endothermic. Gibbs free energy is positive, so the reaction is not spontaneo...
- Tue Jan 26, 2016 3:32 pm
- Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
- Topic: Which is "more ordered"? (9.37)
- Replies: 1
- Views: 1120
Which is "more ordered"? (9.37)
For HW 9.37 part d, the answer key says the 4 moles of solid products are more ordered than the 4 moles of solid reactants. The reaction is 4KCLO3(s) --> 3KCLO4(s) + KCL(s). Why is this the case?
- Sat Jan 23, 2016 6:49 pm
- Forum: Phase Changes & Related Calculations
- Topic: Thermochemistry vs. Thermodynamics
- Replies: 1
- Views: 2176
Re: Thermochemistry vs. Thermodynamics
Thermochemistry is a branch of thermodynamics.
Thermodynamics is the overall study of heat conversions (and other energy forms), while thermochemistry is specifically the study of thermodynamics in regards to chemical reactions.
Thermodynamics is the overall study of heat conversions (and other energy forms), while thermochemistry is specifically the study of thermodynamics in regards to chemical reactions.
- Sat Jan 23, 2016 6:45 pm
- Forum: Calculating Work of Expansion
- Topic: Unit Conversions
- Replies: 2
- Views: 535
Re: Unit Conversions
Multiplying by 101.325J/L atm is basically the same thing as using the gas constants and converting to Joules.
- Fri Jan 15, 2016 11:24 pm
- Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
- Topic: Heat Capacity of a Monoatomic Ideal Gas (9.13)
- Replies: 7
- Views: 1550
Heat Capacity of a Monoatomic Ideal Gas (9.13)
If the heat capacity of a monoatomic ideal gas is Cp = 5/2 R, then for question 9.13, why don't we use this value, as used in 9.7 for part a? Similarly, why is the Cv = 3/2 R value for monoatomic ideal gas used for 9.7, and not for 9.13?
- Sat Jan 09, 2016 8:12 pm
- Forum: Phase Changes & Related Calculations
- Topic: Conditions for Standard Enthalpy
- Replies: 1
- Views: 466
Re: Conditions for Standard Enthalpy
If I understand your question correctly, the "condition" for volume in terms of enthalpy of a reaction is simply that the reaction must occur at a constant volume. As a result, we can say that the enthalpy of a reaction is the same as the change in internal energy.
- Thu Nov 26, 2015 11:45 pm
- Forum: Determining Molecular Shape (VSEPR)
- Topic: Video: Polar vs. Nonpolar?
- Replies: 1
- Views: 514
Video: Polar vs. Nonpolar?
This video explains how to determine if a compound is polar or nonpolar. I hope you like it!
- Wed Nov 18, 2015 9:05 pm
- Forum: Equilibrium Constants & Calculating Concentrations
- Topic: Thermodynamic Stability
- Replies: 1
- Views: 402
Thermodynamic Stability
Hi,
What does it mean to be thermodynamically more stable? My question refers to part c of 11.45, which asks if Cl2 or F2 is more stable, based on their concentrations at 1000K.
Thank you!
What does it mean to be thermodynamically more stable? My question refers to part c of 11.45, which asks if Cl2 or F2 is more stable, based on their concentrations at 1000K.
Thank you!
- Sun Nov 15, 2015 2:20 pm
- Forum: Ideal Gases
- Topic: Online Interactive Module
- Replies: 1
- Views: 713
Online Interactive Module
This online interactive module illustrates different principles regarding PV=nRT.
http://highered.mheducation.com/olcweb/cgi/pluginpop.cgi?it=swf::100%::100%::/sites/dl/free/0023654666/117354/Ideal_Nav.swf::Ideal%20Gas%20Law%20Simulation
http://highered.mheducation.com/olcweb/cgi/pluginpop.cgi?it=swf::100%::100%::/sites/dl/free/0023654666/117354/Ideal_Nav.swf::Ideal%20Gas%20Law%20Simulation
- Tue Nov 03, 2015 6:13 pm
- Forum: Hybridization
- Topic: Hybridization of Lone Pair
- Replies: 1
- Views: 676
Hybridization of Lone Pair
Hi, I have a question about identifying the hybridization of lone pairs in the structure CH2=CHCHO (question six of 2010 midterm). Are we supposed to simply look at the hybridization for the atom by treating the lone pairs as regions of electron density?
- Tue Oct 27, 2015 10:14 pm
- Forum: Ionic & Covalent Bonds
- Topic: 3.79
- Replies: 1
- Views: 824
3.79
Hi, I have a question about 3.79. The question says: "Compounds having bonds with a high covalent character tend to be less soluble in water than similar compounds that have low covalent character. Use ekectonhgatives to predict which of the following compounds is the more soluble in water: (a)...
- Fri Oct 23, 2015 11:45 am
- Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
- Topic: How to distinguish between bonding/antibonding orbitals
- Replies: 1
- Views: 605
Re: How to distinguish between bonding/antibonding orbitals
Hi, As for bonding and antibonding orbitals, look at the electron density. For bonding orbitals, there is an increase in electron density between the nuclei. For antibonding orbitals, there is a decrease in electron density. Also, electrons in the bonding orbitals stabilize the molecules more than e...
- Fri Oct 16, 2015 4:22 pm
- Forum: Lewis Structures
- Topic: Various Lewis Structures
- Replies: 2
- Views: 538
Re: Various Lewis Structures
Generally speaking, the more "correct" Lewis dot structures have minimal formal charges. (Minimal formal charge = more stable)
- Fri Oct 16, 2015 4:14 pm
- Forum: Ionic & Covalent Bonds
- Topic: Diatomic Molecules
- Replies: 3
- Views: 807
Re: Diatomic Molecules
To help remember the diatomic molecules, try "brinclhof."
Br, I, N, Cl, H, O, F
Br, I, N, Cl, H, O, F
- Sat Oct 10, 2015 1:53 pm
- Forum: *Shrodinger Equation
- Topic: Wave Function
- Replies: 3
- Views: 928
Re: Wave Function
Hi, Think of wave functions as a physics concept and orbitals as a chemistry concept. Wave functions are equations that describe the quantum state of a particle. In other words, a wave function is a math function that represents the possible states of a system of particles. Orbitals are wave functio...
- Thu Oct 01, 2015 9:16 pm
- Forum: Empirical & Molecular Formulas
- Topic: F.21
- Replies: 5
- Views: 3103
F.21
Hi, I have a question about number 21 in the F section of the Fundamental Problems. Q: In 1978, scientists extracted a compound with antitumor and antiviral properties from marine animals in the Caribbean Sea. A sample of the compound didemnin-A of mass 1.78 mg was analyzed and found to have the fol...