## Search found 26 matches

Mon Feb 16, 2015 5:55 pm
Forum: General Rate Laws
Topic: Overall Order
Replies: 3
Views: 746

### Overall Order

Hi, I am not sure how to find the overall order. When do we consider the coefficient of other reactants? For example, on page 569 the redox reaction S2O8^2- (aq)+3I-(aq)---> 2SO42- (aq)+I3-(aq) The rate of conception of S2O8^2-=k[S2O8^2-][I-] and the overall order of the reaction is 2. However, the ...
Tue Feb 10, 2015 9:00 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Finding Partial Pressures
Replies: 5
Views: 976

### Re: Finding Partial Pressures

For this same question. How do we know that standard Gibbs free energy is equal to 0, when K=1.00? Do we just set the problem equal to 0 to find T?
Sat Feb 07, 2015 5:08 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Cell Diagram Liquids_Midterm 2014,Q7B
Replies: 1
Views: 330

### Cell Diagram Liquids_Midterm 2014,Q7B

The overall cell reaction: Zn(s)+4H+(aq)+2NO3-(aq)--->Zn2+(aq)+2NO2(g)+2H2O For the cell diagram the answer is Zn(s)|Zn2+(aq)||NO3-(aq),H+(aq)|NO2 (g)|Pt(s) Why was H2O not included in the cell diagram? Are we not suppose to include liquids in the cell diagram? Also, if we have OH- in the balance ce...
Tue Feb 03, 2015 9:18 pm
Forum: Balancing Redox Reactions
Topic: Redox Reaction: prepare orthotelluric acid
Replies: 2
Views: 2569

### Redox Reaction: prepare orthotelluric acid

So I struggled to do problem 13.1 until I finally got an answer, and I tried self testing myself with problem 13.2. However, I am not sure what to do. The problem reads: The following redox reaction is used to prepare orthotelluric acid: Te(s)+ClO3-(aq)+H2O---->H6TeO6(aq)+Cl2(g) a)Identify the eleme...
Thu Jan 22, 2015 7:53 pm
Forum: Administrative Questions and Class Announcements
Topic: Technical Difficulties
Replies: 7
Views: 1200

### Re: Technical Difficulties

I tried Firefox and it did not work, but I tried the other instructions and it works.

Thank you.
:D
Wed Jan 21, 2015 9:55 pm
Forum: Administrative Questions and Class Announcements
Topic: Technical Difficulties
Replies: 7
Views: 1200

### Technical Difficulties

Hi So I am trying to access a video that was uploaded by one of my colleagues, but I can not access it. I am using Google chrome and every time I try to open the link something that reads: "quicktime player was blocked because it was out of date [update plug in..] [run this time]" pops-up....
Sun Dec 14, 2014 12:30 am
Forum: *Titrations & Titration Calculations
Topic: Titrant Equations
Replies: 2
Views: 549

### Re: Titrant Equations

How do you write the equation for a titration problem? The 2011 Final Exam Q#8B mentions NH3 in the question but writes the ICE box equation as NH4(+) + H2O <---> NH3 + H3O+ It also says you have the salt NH4Cl and water. But how do you know that that molecule is formed and why is it not in the equ...
Tue Dec 09, 2014 1:28 am
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: pH of H2O when temperature changes
Replies: 1
Views: 315

### pH of H2O when temperature changes

I was working on problem 11.25, but happened to notice that the temperature is not 25 degrees Celsius, but 37 degrees Celsius. The answer I got is not the same to the answer in the solutions manual. How does the temperature affect the pH? In the course reader the [H30^+] of neutral water at 25 degre...
Tue Dec 02, 2014 10:05 am
Forum: Naming
Topic: Homework Problem 16.29 Part D
Replies: 5
Views: 823

### Re: Homework Problem 16.29 Part D

Lavelle recently posted in this same category with his own thread that states the exact opposite. viewtopic.php?f=45&t=1409 Which form is correct? Lavelle's post is from 2011. They (scientist? or someone) updated the rule so instead of having the anionic compound first it would be the neutral c...
Tue Dec 02, 2014 12:52 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Quiz #2, Problem 10
Replies: 7
Views: 2483

### Re: Quiz #2, Problem 10

tchar96_1F wrote:Why isn't it -2x, +x, +x?

When you remove BrCl it will cause the formation of more reactant; the amount of the products decrease by the molar ratio (Le Chatelier's principle)
Tue Dec 02, 2014 12:32 am
Forum: Naming
Topic: Homework Problem 16.29 Part D
Replies: 5
Views: 823

### Re: Homework Problem 16.29 Part D

This part asks us to write the formula for sodium bisoxalato(diaqua)ferrate (III) and I have two questions about this. Why is the bisoxalato written before diaqua? Shouldn't they be ordered alphabetically without regard for the prefixes? Also, the answer to the question is Na[Fe(OH2)2(C2O4)2]. Why ...
Mon Dec 01, 2014 10:22 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Quiz #2, Problem 10
Replies: 7
Views: 2483

### Re: Quiz #2, Problem 10

No, I got 0.2469 and -0.88
You would not use the negative value you would plug in the positive value.
Mon Dec 01, 2014 9:05 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Homework Question 69
Replies: 5
Views: 763

### Re: Homework Question 69

Hi, how do you find the volume of the container with the values that are given? What formula do we use? Can someone please help. Thanks in advance.
Mon Dec 01, 2014 8:56 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Quiz #2, Problem 10
Replies: 7
Views: 2483

### Re: Quiz #2, Problem 10

Yes, 0.54 is the "initial value" after 1.08 is divided by 2 for BrCl you can then use the ice box and put 0.54 as the initial molar concentration to find the new partial pressure. I : BrCl 0.54, Br2 4.9, Cl2 7.6 C (use the molar ratio):+2x, -x, -x E: (0.54+2x), (4.9-x) (7.6-x) K(initial co...
Sat Nov 29, 2014 11:41 am
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Module 2
Replies: 3
Views: 927

### Module 2

I am not sure how to approach this problem: A researcher fills a 1.00 L reaction vessel with 1.84 x 10-4 mol of BrCl gas and heats it to 500 K. At equilibrium, only 18.3 % of the BrCl gas remains. Calculate the equilibrium constant, assuming the following reaction is taking place. 2BrCl(g) ⇌ Br2 (g)...
Sat Nov 22, 2014 3:19 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Demo: Dimerization of Nitrogen Dioxide
Replies: 1
Views: 833

### Demo: Dimerization of Nitrogen Dioxide

The demo shown in class nitrogen dioxide was heated (amber) and dinitrogen tetraoxide was cooled (clear). When nitrogen dioxide is heated why does it have an exothermic reaction? Is it because heat forms an “excessive” amount of product and the reaction is trying to minimize the change; therefore, i...
Sun Nov 09, 2014 2:58 am
Forum: Determining Molecular Shape (VSEPR)
Topic: Drawing AX2E2 Shape
Replies: 2
Views: 799

### Re: Drawing AX2E2 Shape

I suggest putting the lone pairs adjacent to each other because if you put the lone pairs across each other you might confuse the shape. The lone pairs adjacent to each other indicates that the molecule is bent and not linear.
Thu Nov 06, 2014 1:14 pm
Forum: Polarisability of Anions, The Polarizing Power of Cations
Topic: 2.79
Replies: 1
Views: 770

### 2.79

Arrange the cations Rb+, Be2+, and Sr2+ in order of increasing polarizing power.

I thought the arrangement was Rb+<Be2+<Sr2+ but the answer is Rb+< Sr2+<Be2+
Mon Nov 03, 2014 12:14 am
Forum: Ionic & Covalent Bonds
Topic: Problem 2.19
Replies: 1
Views: 2145

### Re: Problem 2.19

Give the ground-state configuration and number of unpaired electrons expected for each of the following ions: For this question, I am just confused on how do we know the expected unpaired electrons. a.) Sb3+ b.) Sn4+ a) First, write down the ground state configuration of Sb: [Kr]4d10 5s2 5p3 then, ...
Sun Nov 02, 2014 11:46 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Determining the position of a lone pair
Replies: 2
Views: 1385

### Re: Determining the position of a lone pair

When determining the shape of a molecule with a lone pair, how do you determine the position of the lone pair and thus decide which part of its overall shape to remove to determine the shape of the atoms without the lone pair? For example, in the molecule TeCl4, why do we place the lone pair in a p...
Sun Nov 02, 2014 11:27 pm
Forum: Lewis Structures
Topic: HW 2.55/Identifying where to put atoms in a lewis structure
Replies: 1
Views: 414

### Re: HW 2.55/Identifying where to put atoms in a lewis struct

Question 2.55: Write the Lewis structure, including typical contributions to the resonance structure (where appropriate, allow for the possibility of octet expansion, including double bonds in different positions), for (a) sulfite ion; (b) hydrogen sulfite ion; (c) perchlorate ion; (d) arsenate ion...
Sun Nov 02, 2014 11:12 pm
Forum: Lewis Structures
Topic: Question 2.33c
Replies: 2
Views: 411

### Re: Question 2.33c

Nitrogen and Fluorine can not form a double bond since Flourine has 7 valence electrons and it only needs 1 electron to obtain an octet (Fluorine does not form double bonds).
Sun Nov 02, 2014 11:00 pm
Forum: Resonance Structures
Topic: Most Important Resonance Structures?
Replies: 1
Views: 371

### Re: Most Important Resonance Structures?

Yes, the "most important" resonance structure is when the central atom is 0 (the central atom is stable). Your second questions defines resonance hybrid, which is when the electrons are delocalized (structures are an approximation of the electrons locations). I think you will always have a...
Sun Nov 02, 2014 10:29 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: When there are two central atoms
Replies: 3
Views: 4131

### Re: When there are two central atoms

No it does not have a resonance. Hydrogen can not gain electrons.
Sun Nov 02, 2014 8:39 pm
Forum: Dipole Moments
Topic: Dipole Moment Arrows
Replies: 5
Views: 1833

### Re: Dipole Moment Arrows

No, the dipole (arrow ) still points toward the negative charge.
Sun Nov 02, 2014 8:16 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: When there are two central atoms
Replies: 3
Views: 4131

### Re: When there are two central atoms

How do you name your lewis structure and classify its shape using VSEPR when there are two central atoms? (ie. 29a in chapter 3) #29a. C2H4 To determine the lewis structure first figure out the number of valence electrons. C has 4 (valence electrons) x2 carbons present=8 valence electrons H has 1 (...