## Search found 23 matches

Sat Mar 18, 2017 12:11 pm
Forum: Balancing Redox Reactions
Topic: How to determine Galvanic Cell molecules
Replies: 2
Views: 406

### Re: How to determine Galvanic Cell molecules

So essentially, for the cathode we want the greatest positive value and for the anode we want the greatest negative value?
Fri Mar 10, 2017 11:16 pm
Forum: *Free Energy of Activation vs Activation Energy
Topic: equilibrium constants and free energy [ENDORSED]
Replies: 1
Views: 855

### equilibrium constants and free energy[ENDORSED]

When K=0 what does this mean in terms of free energy?
Mon Mar 06, 2017 10:00 am
Forum: *Nucleophilic Substitution
Replies: 6
Views: 1659

A double headed arrow is used in the case when 2 electrons are getting passed. This is why we normally use a double-headed arrow. A single headed arrow is a little less common as it refers to only 1 electron getting passed. When dealing with bonds we are typically dealing with 2 electrons which is w...
Wed Feb 22, 2017 12:08 pm
Forum: Method of Initial Rates (To Determine n and k)
Topic: 2 step reactions
Replies: 1
Views: 302

### 2 step reactions

For a two step reactant how do we know which one is slower?
Mon Feb 20, 2017 8:16 am
Forum: Method of Initial Rates (To Determine n and k)
Topic: Differntial rate law vs. Integrated rate law
Replies: 1
Views: 306

### Differntial rate law vs. Integrated rate law

I just wanted to clarify that we use the integrated rate law when we are trying to identify a change in [A] and then we can use the differential rate law for everything else? Is this true?
Sat Feb 11, 2017 7:06 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: Changes in both volume and temp [ENDORSED]
Replies: 5
Views: 844

### Changes in both volume and temp[ENDORSED]

If we are given a problem that provides us with both an initial volume and temp and a final volume and temp do we have to calculate deltaS for both of these or will 1 calculation of deltaS suffice? I am confused on if we do both S=nCln(T2/T1) and S=nCln(V2/V1)? Thank you very much in advance
Sun Jan 29, 2017 11:11 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Bond Enthalpies
Replies: 3
Views: 413

### Re: Bond Enthalpies

If we are given the bond enthalpies for a molecule, but there is multiple moles of that molecule would we multiply the bond enthalpy by the number of moles? Thank you in advance!
Sat Jan 28, 2017 9:07 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: Entropy
Replies: 7
Views: 734

### Re: Entropy

If entropy is always increasing, then in a non-spontaneous reaction what part of the reaction relates to the increase in entropy if we are using work to create order?
Sat Jan 21, 2017 8:58 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Homework Question: 8.49
Replies: 1
Views: 326

### Homework Question: 8.49

For question 49 in the homework we have to use the equation deltaU=deltaH-PdeltaV to solve for the internal energy. I found H and PV (using the ideal gas equation) and I subtracted them but since PdeltaV was a negative value I ended up getting -318-(-2.47)=-315.53; however, the book got -318-2.47=-3...
Fri Jan 13, 2017 12:36 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Standard Enthalpy of Formation Question
Replies: 3
Views: 424

### Re: Standard Enthalpy of Formation Question

In the example in the course reader, we were given the deltaH of the rxn (-555.38) . Will we always be given this and then just adjust it based on the amount of moles, etc.?
Fri Jan 13, 2017 12:32 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Bond Enthalpies
Replies: 7
Views: 550

### Re: Bond Enthalpies

In the course reader when we are looking at method two, all the bond enthalpies are in kJ.mol^-1. However after we add them all up, the units are kJ so I am curious on what happened to the mol^-1?
Fri Jan 13, 2017 12:27 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: standard reaction enthalpy
Replies: 2
Views: 304

### Re: standard reaction enthalpy

In general, what action do we take when the reaction is not in its standard state?
Fri Dec 02, 2016 12:29 pm
Forum: Polyprotic Acids & Bases
Topic: Fall 2012 Final Exam Question 8
Replies: 1
Views: 472

### Fall 2012 Final Exam Question 8

In problem 8 from the 2012 final exam, I understand that we carry over the 4.0x10^5 mol*L^-1 because that is how many H+ atoms are generated in the first dissociation. However, because we end with the same amount of H+ ions after the second reaction, I am confused on if HCO3 generated any H+ ions?
Mon Nov 21, 2016 1:15 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Strong/weak acids
Replies: 6
Views: 2029

### Re: Strong/weak acids

If we are given a problem that has a Ka or a Kb then we automatically know it's weak, correct? Since strong acids and bases fully ionize? Thank you!
Mon Nov 21, 2016 1:12 pm
Forum: Amphoteric Compounds
Topic: Amphoteric vs amphiprotic
Replies: 6
Views: 20148

### Re: Amphoteric vs amphiprotic

I see how it relates since the Bronsted definition of an acid is that it can give off a proton, but essentially that's what it says an Amphoteric compound does too. So I guess my question is why would the amphiprotic compounds directly related to the Bronsted definition and not amphoteric? Sorry for...
Mon Nov 21, 2016 1:09 pm
Forum: Amphoteric Compounds
Topic: Amphoteric vs amphiprotic
Replies: 6
Views: 20148

### Re: Amphoteric vs amphiprotic

I was talking with some classmates and they said amphiprotic kind of relates to the Bronsted definition of acids and bases? How is this so? Thank you
Sat Nov 12, 2016 10:19 am
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Coordinate Number
Replies: 3
Views: 609

### Re: Coordinate Number

hello,
I am also a bit confused on coordination numbers too. Just to clarify, if we had the compound [Co(NH3)5Cl]Cl then the coordination number would be 6 since there are 6 donor atoms sticking to the cobalt?
Sat Nov 05, 2016 12:09 am
Forum: Hybridization
Topic: Regions of Electron Density & Naming Hybrid Orbitals
Replies: 3
Views: 399

### Re: Regions of Electron Density & Naming Hybrid Orbitals

Do we count loan pairs as regions of electron density? I know we do not typically draw them in Lewis structures but I am not sure about counting them in hybridization. Thank you!
Mon Oct 24, 2016 5:05 pm
Forum: Electronegativity
Topic: Trends in periodic table
Replies: 6
Views: 860

### Trends in periodic table

On Quiz 2 preparation problem #5 it asks us to pick the atom with highest electron affinity. However, they give us a noble gas and I am not sure if the trends of the periodic table are applied to the noble gases since they aren't reactive? Thank you!
Fri Oct 21, 2016 9:19 am
Forum: Formal Charge and Oxidation Numbers
Topic: How to figure out formal charge? [ENDORSED]
Replies: 6
Views: 1078

### Re: How to figure out formal charge?[ENDORSED]

When figuring out a formal charge do we count the individual electrons that are shared or the pairs of electrons that are shared or lone?
Sun Oct 16, 2016 8:28 pm
Forum: Lewis Structures
Topic: Resonance [ENDORSED]
Replies: 5
Views: 684

### Re: Resonance[ENDORSED]

I am also confused on resonance. Does resonance in one species continue when it is bonded to another species? For example, Say NO3 were to bond with another molecule. Would the nitrogen prefer a bond to a specific oxygen when other molecules come into play, or would that not matter and any Lewis str...
Fri Oct 07, 2016 5:55 pm
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Electron Configuration [ENDORSED]
Replies: 4
Views: 554

### Re: Electron Configuration[ENDORSED]

I am a little confused about the Diagram on page 63 of our course reader. For an electron with n=3 and l=2 we get a d orbital, but how do we get the numbers -2,-1, 0, 1, 2 in the 5 boxes representing 3d? Thank you!
Tue Sep 27, 2016 12:39 pm
Forum: Balancing Chemical Reactions
Topic: How familiar should we be with Naming compounds? [ENDORSED]
Replies: 8
Views: 1655

### How familiar should we be with Naming compounds?[ENDORSED]

In some of the homework questions, I noticed it will write out names of compounds and ask us to write and balance the chemical equation. This made me wonder if I should be expected to know naming. If yes, does any one know any good resources (along with the course reader) for me to review this? Than...