## Search found 21 matches

Sat Mar 12, 2016 4:34 pm
Forum: *Cyclohexanes (Chair, Boat, Geometric Isomers)
Topic: Equatorial and Axial vs Cis and Trans
Replies: 1
Views: 1025

### Re: Equatorial and Axial vs Cis and Trans

Cis and trans are determined by if the molecules are up or down in relation to the ring. Both the equatorial and axial positions can be either up or down. To be cis, they must be either both up or both down, regardless of if they are both equatorial, both axial, or one of each. To be trans, one is u...
Sun Mar 06, 2016 2:14 pm
Forum: *Alkanes
Topic: 2011 Final 1C Higher Heat Capacity?
Replies: 2
Views: 397

### 2011 Final 1C Higher Heat Capacity?

Question 1C on the 2011 final asks if ethane or ethene has the higher heat capacity. How do we determine this?
Sun Feb 21, 2016 8:35 pm
Forum: Arrhenius Equation, Activation Energies, Catalysts
Topic: 15.65 Effect of temperature on k
Replies: 1
Views: 410

### 15.65 Effect of temperature on k

IPart c of 15.65 asks what will be the effect of raising the temperature on k. The solutions manual states that raising the temperature will increase the rate constant of the reaction with he higher activation barrier more. Why is this?
Sat Feb 06, 2016 3:20 pm
Forum: Interesting Applications: Rechargeable Batteries (Cell Phones, Notebooks, Cars), Fuel Cells (Space Shuttle), Photovoltaic Cells (Solar Panels), Electrolysis, Rust
Topic: 14.55 How to determine cathode and anode?
Replies: 1
Views: 570

### 14.55 How to determine cathode and anode?

In this problem NiSO4 is electrolyed. How do we know that Ni is the cathode and not the anode? Also, the anode equation is 2H20->O2+4H+4e-, which is reversed from the equation given in appendix 2b, yet the sign was not changed on the value for E. Shouldn't you change the sign when you reverse a reac...
Sat Feb 06, 2016 12:42 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Solubility Product
Replies: 1
Views: 346

### Solubility Product

Problem 14.45 asks about the solubility product. What is this and how do we calculate it?
Tue Feb 02, 2016 1:26 pm
Forum: Balancing Redox Reactions
Topic: Acid vs Base Solution
Replies: 1
Views: 281

### Acid vs Base Solution

What do you do differently when balancing a redox reaction when the solution is acidic vs when it is basic?
Fri Jan 22, 2016 7:59 pm
Forum: Calculating Standard Reaction Entropies (e.g. , Using Standard Molar Entropies)
Topic: Determining Higher Molar Entropy 9.27
Replies: 2
Views: 574

### Determining Higher Molar Entropy 9.27

How do you determine if HF or HBr has the higher molar energy in part a of 9.27? They both are gasses and have only two atoms, so I do not know what to compare.
Mon Jan 18, 2016 3:51 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Standard Enthalpy of Formation=0?
Replies: 2
Views: 458

### Standard Enthalpy of Formation=0?

Why is the standard enthalpy of formation for O2 and other compounds zero?
Thu Jan 14, 2016 4:19 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: 8.31 heat released by Krypton gas
Replies: 3
Views: 980

### Re: 8.31 heat released by Krypton gas

Where did you get 5/2R and what is R?
Tue Jan 12, 2016 4:55 pm
Forum: Phase Changes & Related Calculations
Topic: Equation W=delta U-q in problem 8.7
Replies: 1
Views: 404

### Equation W=delta U-q in problem 8.7

In homework problem 8.7 the equation used to find how much work was done is W=delta U- q. Is this a standard equation or was it made by combining others? I wasn't able to find it anywhere. Can someone explain where it came from and how we use it?
Mon Nov 30, 2015 5:35 pm
Forum: Lewis Acids & Bases
Topic: Boron Trifluoride, BF3
Replies: 4
Views: 1570

### Re: Boron Trifluoride, BF3

What I told you isn't right...
The 3 F's each attach to B with a single bond because B cannot have an expanded octet, which means that B only has 6 electrons when it should have 8 to fill its outer shell. B has to accept more electrons to fill the octet, and Lewis acids accept electrons.
Sun Nov 29, 2015 11:53 am
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Fundementals J15 NaC6H5O is acid/base?
Replies: 4
Views: 2681

### Fundementals J15 NaC6H5O is acid/base?

In this problem you are given NaC6H5O and are asked to write the equation for the proton transfer with water. How do you know that this compound is a base and should gain an H+ proton?
Sat Nov 28, 2015 11:33 pm
Forum: Lewis Acids & Bases
Topic: Boron Trifluoride, BF3
Replies: 4
Views: 1570

### Re: Boron Trifluoride, BF3

Yes, the reason it is a Lewis acid is because BF3 must accept one more pair of electrons to have a full octet. This means that it will gain an H atom, so the pH will be lower because there is more hydrogen present.
Tue Nov 17, 2015 9:34 pm
Forum: Naming
Topic: -ide ending on anions
Replies: 1
Views: 415

### -ide ending on anions

Why is it that some anions have the -ide ending when others just use the name of the element? For example, why is [Ni(NH3)Cl]Cl2 pentaamminechloronickel(III) chlorIDE instead of chlorine?
Sat Nov 14, 2015 4:03 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Decreasing Partial Pressure
Replies: 2
Views: 490

### Re: Decreasing Partial Pressure

If you decrease the partial pressure of the reactants, then there will be more products comparatively. This will cause the reaction to produce more reactants to get back to equilibrium.
Thu Nov 12, 2015 7:46 pm
Forum: Ideal Gases
Topic: HW problem 11.39 using chart 11.2?
Replies: 1
Views: 385

### HW problem 11.39 using chart 11.2?

This problem gives you the equation 2BrCl+H2-->Br2+2HCl and says to use chart 11.2 to find K at 300 without giving any other information. The chart does not have this equation on it, so I don't know how to go about the problem. It does have some equations that are similar on it, so are we supposed t...
Tue Oct 27, 2015 10:31 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Linear Molecular Geometry
Replies: 2
Views: 586

### Re: Linear Molecular Geometry

I believe if there are two lone pairs then it is linear because the force of each pair opposes the other, but if there is only one pair then it will be bent.
Fri Oct 23, 2015 10:21 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Formal Charge
Replies: 1
Views: 270

### Re: Formal Charge

Formal charge is the charge of each individual atom in the molecule. Formal charge assumes that the bonded electrons are shared equally between the two bonded atoms. To find it, you take the number of valence electrons for the atom, which you find from the periodic table, and subtract from it the nu...
Sun Oct 18, 2015 5:04 pm
Forum: Properties of Light
Topic: Homework problem 3.57
Replies: 2
Views: 451

### Homework problem 3.57

In part C of this problem the Cl in the perchlorate ion is able to have an expanded octet with 7 pairs of bonded electrons. Why is this possible? How do you know which elements can have an expanded octet and how many bonds are possible?
Sat Oct 10, 2015 1:49 pm
Forum: Properties of Light
Topic: Homework problem 2.43
Replies: 1
Views: 479

### Homework problem 2.43

For the electron configuration of tungsten I got [Xe] 5d4 6s2. Why does the answer include 4f14?
Thu Oct 01, 2015 9:52 am
Forum: Properties of Light
Topic: De Brogile's Equation [ENDORSED]
Replies: 3
Views: 728

### Re: De Brogile's Equation[ENDORSED]

Yes, it must be converted to kilograms for the equation to work