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 * Welcome to the WTHS AP CHEMISTRY BLOG... **

January 30, 2012: Introduction to Spontaneity and Entropy (LaBelle)


January 31, 2012: Temperature and Spontaneity (Adam Adnane) - These Are The Notes We Took Today in Class. - Our Homework Was pg. 897 #12-29 Even, 33, & 34 All Answers Are On pg. A-39 (Except 34, Doing One Alone Is Good Practice Right)  


 * 1/31/12** **KEVIN MILLER**

Well i dont know how to do that so i guess i have to type my notes.. **>:(**

Temperature & Spontaneity


 * Entropy changes in the surroundings are determined by the heat flow
 * An Exothermic Process is favored (more likely to happen) because by gving up heat the entropy of the surroudings increases
 * Exothermic Processes = more likely to be spontaneous
 * /\S = change in entropy
 * The size of **/\Ssurr = -/\Hsys / T**
 * /\S is measured in J/mol*K

/\S increases if ...
 * Temperature increases
 * Solids or liquids dissolve
 * Solid → Liquid, Solid → Gas , Liquid → Gas
 * Dissolved gases escape soultion
 * Molar Mass increases
 * Molecular Complexity Increases

The Homework for 5th period was Page 897 12-29 odd and 33-34...

//5th PERIOD CHEMISTRY JOKEE OF THE DAY!!!!//
 * Q**: What is the chemical symbol for diarreha???
 * A**: (CO(NH2)2)2


 * Explanation**: Urea is the molecule CO(NH2)2. The prefix "di" stands for two.

2/1/12 Joe Lutz Pd. dos Today we took notes on Gibb's Free Energy. There was no homework but there's a web assign due FRIDAY AT MIDNIGHT. Here's my notes... Gibb's Free Energy Third Law of Thermo. Free Energy in Rxn's That is all haha... CYAnide BROmine
 * Defined as Enthalpy of a system minus the product of the temperature times the entropy of the system.
 * ΔG=ΔH-(T*ΔS) ; Where G is G.F.E., H is Enthalpy, T is Temperature, S is Entropy
 * ΔS= (-ΔG)/T
 * If ΔG is negative at constant temp and pressure then the process is Spontaneous
 * Heres an ex. from class...
 * The entropy of a pure crystal at 0 degree kelvin is 0.
 * Since we cannot reach that temperature all other entropies must be > 0
 * Standard Entropies are when the substance is at 298K and 1atm
 * Products- Reactants= ΔS
 * More complex the molecule, the greater ΔS
 * Gibb's Free energy can be calculated but not measured
 * Use Hess's law with known reactants

Lindsey Koch Period 5 2/1/12 Here are the notes from today. No homework due tomorrow, just a WebAssign due Friday!

__Gibb's Free Energy__ > > Remember units! > ΔH= kJ/mol > ΔS= J/mol K > T= K >
 * G=H - TS
 * Never used this way
 * ΔG= ΔH - TΔS at constant temperature
 * Divide by -T
 * -ΔG/T = -(ΔH/T)+ΔS
 * -ΔG/T = -ΔSsurr+ΔS
 * -ΔG/T = ΔSuniv
 * If ΔG is negative at constant T and P, the Process is spontaneous


 * Check!** [[image:wths-labelle/IMG_0245.JPG width="640" height="154"]]



__Third Law of Thermo__ ΔH^0rxn=Hprod - Hreact and ΔS^0rxn=Sprod - Sreact therefore, ΔG^0rxn=Gprod - Greact
 * The entropy of a pure crystal at 0 K is 0.
 * Gives us a starting point
 * All others must be > 0
 * Standard Entropies S^0 (at 298 K and 1 atm) or substances are listed
 * Products-reactants to find S^0



JOKE OF THE DAY! Q: What is the name of the molecule CH2O? A: Seawater

**Free Energy Pressure** 02-08-2012 MJ Alanis

**Notes**
∆G = ∆G'+ RTln(Q) ====*where (Q) is the reaction quotients (Pressure of the products raised to its coefficient/ Pressure of the reactants raised to its coefficient) ====

Example
<span style="font-family: Arial,Helvetica,sans-serif; font-size: 130%;">If you were given...

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 130%;">to find the Q you'd arrange it like so.. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 130%;">

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 130%;">//Example//
<span style="font-family: Arial,Helvetica,sans-serif; font-size: 130%;">CO(g) + 2H2(g) -> CH3OH(l)

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 130%;">Question: <span style="font-family: Arial,Helvetica,sans-serif; font-size: 130%;">Would this be spontaneous at 25 degrees Kelivin with H2 at a pressure of 5 atm and CO at a pressure of 3 atm?

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 130%;">ΔG of formation for CH3OH(l) = 166 KJ

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 130%;">So... ΔG= -166- [-137] which equals -29

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 130%;">Now use ∆G = ∆G'+ RTln(Q)

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 130%;">∆G = (-29) + (8.314(298)ln(1/(5^2)(3)) <span style="font-family: Arial,Helvetica,sans-serif; font-size: 130%;">∆G = (-29) + (-10696.88) <span style="font-family: Arial,Helvetica,sans-serif; font-size: 130%;">∆G = -10725.88 KJ/mol

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 130%;">Because ∆G is neagtive the reaction is SPONTANEOUS

Chem Joke of the Day
 * Q:** Why did the chemist sole and heel his shoes with silicone rubber?
 * A:** To reduce his carbon footprint.

JASON RIVERA What's Equal At Equilibrium
 * Initially there's only A & B son only forward rxn is possible
 * As C & D build up, reverse rxn speeds up as forward rxn slows down
 * Eventually rates are equal
 * Rates
 * Concentrations are not
 * Rates are determined by concentrations and activation energy
 * Concentrations do no change at equilibrium or in slow reactions
 * Remember No Units for K

CHEMISTRY JOKE OF THE DAY!!!!!!!!!!!!!!!!!!!!!!!!

Q: What do you do with a dead chemist? A: Barium

=**MAURA CARR** pd. 2= potashum ^EXAMPLE PROBLEM!
 * remember, NO UNITS in the answer!
 * this symbol means __prime__
 * remember, K and Q are the same thing!

chem joke of the day!!!Gold walks into a bar, barman shouts Au get out of here!

LAURA ZIMMERMANN PD. 2 ! Here are the answers from the book work we were working on in class last week(: Pgs. 759-760 #'s 17.7-17.23

<span style="font-family: Georgia,serif;">February 21, 2012: //__**Reaction Quotient & Solving Equilibrium Problems**__// (Adam Adnane) <span style="font-family: Georgia,serif;">- These Are The Notes We Took Today in Class. <span style="font-family: Georgia,serif;">-For the last equation, after you solve for x using the quadratic equation you end up w/ 2 X's we will discuss which of these is correct tomorrow in class. <span style="font-family: Georgia,serif;">

<span style="font-family: Georgia,serif;">Chem Joke of the Day: Two atoms are walking down the street. One atom says to the other, "Hey! I think I lost an electron!" The other says, "Are you sure??" It responds, "Yes, I'm positive!"

Tyler Lee pd. 5 Equilibrium constant Rxn quotient Using Kp=Kc(RT)^delta n





Chem Joke

What did Neekolai lai, Nee, Nee, kolai, say to Johnny on christmas?

I know you wanted a pair of slacks but they argon right now and we have to buy some more. MAGNESIUM

Will Walters Period 2

I don't know how to turn it right side up so its staying like this...and homework is p 760 #28-36 even and #37



Conner Meenan pd. 5Classwork: pg. 760 #27-35 odd Homework: pg. 760 #28-36 even & 37

<span style="color: #f5000a; font-family: Georgia,serif; font-size: 120%;">Reminders: 1. When calculated the change in moles for an equilibrium equation, only calculate using gases! <span style="color: #f5000a; font-family: Georgia,serif; font-size: 120%;">2. When determining the direction of the reaction, always go the opposite way that the arrow is pointing! <span style="color: #f5000a; font-family: Georgia,serif;"> ex: Q < K ... Since the arrow (<) is facing left, this means that the reaction must move to the right, and vice vers a

<span style="font-family: Georgia,serif; font-size: 120%;">Classwork:

Harry Betz equilibrium problems
 * <span style="color: #ff00d1; font-family: Georgia,serif; font-size: 130%;">Chemistry Joke of the Day: **





Helium walks into a bar, The bar tender says "We don't serve noble gasses in here." Helium doesn't react.

2/29/2012 __Le Chatelier's Principle__ (Davis Perchik)

 * =====If a stress is applied to a system, the position at equilibrium shits to reduce stress=====
 * There are 3 types of stress

Change amounts of reactants and/or products

 * Adding products makes Q>K, so the reaction goes to the left
 * Removing reactants makes Q>K, so the reaction goes to the left
 * Adding reactants makes Q<K, so the reaction goes to the right
 * Removing products makes Q<K, so the reaction goes to the right

Chemistry Joke of the day: What's the difference between Chemistry and cooking? In Chemistry, you should never lick the spoon.

2/29/2012 (Eric Ling) ‍‍‍‍ Chemistry Joke of the Day:

*AP Exam Reminders*

1. The cost of a SINGLE AP Exam is $87. (same as last year) 2. The final date to pay for the AP Exams is March 30th! (unless you want to pay extra) 3. In order to buy a test past the date of March 30th, an additional $50 dollars is required! 4. Make sure that you circle the tests that you are taking! 5. Don't wait until the last minute to pay for the testing! 6. Mrs. Labelle's birthday is the same day as the AP Chemistry Exam! :) 7. If taking multiple tests, and you are in need of financial assistance talk to Ms. Babbins or Mr. Fafara in the guidance office!

JEFF DECHRISTOPHER! period 5








 * HOMEWORK IS ABOVE WITH THE ANSWER TO NUMBER 63 BUT DONT COPY IT BECAUSE IT MIGHT NOT BE CORRECT**


 * CHEMISTRY JOKE(S)!!!!!**


 * Q:** Anyone know any jokes about sodium?
 * A:** Na


 * Q:** Why was the mole of oxygen molecules excited when he walked out of the singles bar?
 * A:** He got Avogadro's number!

Hannah Washam period 2 its late i know :( Change in Pressure
 * No change in Kc
 * Change the pressure by
 * Adding an inert gas
 * Partial Pressures of reactants and product aren’t changed
 * No effect on equilibrium position
 * Changing concentration of gaseous components
 * Changing volume
 * A decrease in volume increase in pressure
 * System will move in the direction that has the least moles of gas
 * ∆n=0 no shift

Change in Temperature The Van’t Hoff Equation ln(K2/K1)=-∆Hrxn(1/T2-1/T1) __PAUL TAUFALELE PERIOD FIVE 5, 3/12/2012 acids and such.__
 * Kc changes
 * Doesn’t just change equilibrium position, changes equilibrium constant
 * Direction of the shift depends on whether it is exothermic or endothermic
 * Exothermic
 * ∆H<o
 * Releases heat
 * Raising temperature push towards reactants
 * Shifts to left
 * Endothermic
 * Absorbs heat
 * Raising temperature push toward products
 * Shifts to left
 * The effect of temperature on K
 * K1 is equilibrium constant @ T1
 * K2 is equilibrium constant @ T2
 * Use Thermodynamic R





CHEMISTRY JOKE O THE DAY Potashum

//**__Christian Diamond's super fantastic turn to blog. 3/12/12 Acids/Bases/pH!!!__**//

Good evening ladies and gentlemen of AP chemistry. Unfortunately I lack the technology most of you enjoy, so I'm going to have to retype my notes. Oh joy. Well, without further ado, let us begin.

Let's begin with with some acid and base stuff

__Arrhenius definition:__ Mr. Arrhenius said that... -Acids produce H+ ions in water -Bases produce OH- ions in water These statements are not necessarily false, they are just lacking. This limits us to only aqueous solutions and only one kind of base. An example of why this lacking is that ammonia (NH3) would not be a base according Mr. Arrhenius. However, ammonia is indeed a base.

Since this guideline for determining acids and bases was lacking, two others took it upon themselves to settle this.

__Bronsted-Lowry definition:__ These gentlemen have provided us with a much more accurate set of rules to go by, and they are.... -An acid is a proton (H+) donor -A base accepts said proton -Acids and bases come in pairs Example time!

HCl + H2O <--> H3O+ + Cl-

In this particular example, HCl acts as our acid, and water as our base. Water is unique because due to the fact that is both a H+ ion and a OH- ion, it can serve as an acid or a base. We then have the hydronium ion and a Cl- ion. My little <--> is supposed to be the equilibrium thing.

__Acid-base pairs:__ As our fine fellows Bronsted and Lowry said, acids and bases come in pairs. To better explain this I will sort of go off on a tangent and explain the general equation for acid-base reactions first

__General Equation:__

HA + H2O <--> H3O+ + A-

A is not an actual element, mind you, its just sort of a placeholder. It can be any element, or ion if it wants to be. Nobody tells A what it can't do. There is another way to write it, however it is very similar, and unless my instincts betray me, I believe it has something to do with just taking the water out of the equation, as it is liquid and we do not concern ourselves with such states of matter in equilibrium. I would put the other equation here, but the internet is not helpful and this bothersome equation SLIPS MY MIND. continuing onward..

For our general equation, HA would represent our acid, H2O is our base, Hydronium is our conjugate acid and the A- is our conjugate base. Conjugate means to be joined together, so we say the conjugate base of HA would be A-. We keep those two together because they share that A. A is good.

__The acid dissociation constant Ka:__ Our old friend K returns with a new lease on life as Ka. It's actually K sub a, however I'm quite bad with this new fancy technology and I do not know how to properly subscript here. SO DEAL WITH IT. Ahem, moving onward, we find the our new K the same way as old K. Simply take the concentrations of the products over the concentrations of the reactants. I'll give you an example using the general equation.

Ka = __[A-] * [H3O-]__ [HA]

Notice that I left out water? That goes back to the thing I mentioned earlier about water not being important because we only concern ourselves with aqueous parts of the equation.

__Strong acids:__ Finally we get to something fun! There are seven strong acids. These are HCl, HI, HBr, H2SO4, HNO3, HClO3, and HClO4. This acids dissociate completely in water, meaning that there is virtually no equilibrium, the reaction shifts all the way to the products side. This also means they have a quite a large K. They also form extremely weak conjugate acids, weaker than even water. The concentration of H+ ions is practically the same as that of your original acid.

__Weak acids:__ Basically everything opposite of strong acids. They hardly dissociate, due to stronger bonds between the proton and whatever it has bonded with. The concentration of your acid is much higher than that of the H+ ions, so your K is quite small. As you probably would have guessed, weak acids make strong conjugate bases.

__Types of acids:__ There are a few different varieties of acids, each a bit different. -The first is monoprotic, having only one acidic hydrogen, such as HCl -We have polyprotic, having more that one acidic hydrogen, such as H2SO4 or H3PO4 -Finally we have the organic acids, which contain the carboxyl group, or COOH, with the H attached to an O. As a side note, these acids are normally pretty weak.

__pH scale:__ The last section deals with pH, which is a way to tell the general potency of an acid or base. Acids have low ratings, while bases have high ratings. Now, some equations.

pH = -log[H+] this is used for acids. pOH = -log[OH-] this is for bases pKa = -logK

Some more side notes. say if your concentration for H+ was 1 X 10^-7, then your pH would be 7.00, as we include two significant figures. If you don't have one raised to a power, your pH should still be close to your exponent anyway. Also, pH + pOH always equals 14.

Before I end this, I leave you with some chemistry jokes

Two atoms were walking down the street when one turns to the other and says, "I think I've lost an electron!" The second asks, "Are you sure?", to which the first replies, "I'm positive!"

I'd put more for you, but it seems all the good jokes ARGON!

**Jerry Littrell Period 5 3/13/12** GET READY!
This is from the homework we were assigned on 3/12/12

e sure not to do what I did REMEMBER there will be 2 moles of OH so in #2 so .0745 has to be doubled continued.......

Now for some notes we took in class: continued.... Now how about a little joke Why does a chemist hate the day rates? -Because the nitrates are cheaper. tee hee ha ha.............

=More Notes on Acids and Bases= Matt Lowenthal I do realize these are all pretty crappy quality pictures. If anyone needs me to re-post using a better camera I will try to. =Homework for tonight is PG 807 24, 28, 44, 48, 64, and 68= Unfortunately I have very limited amount of imagination so there is no joke today for 2nd ap chemistry.

Nick Wiest's post son Even more unfortunately I am a caveman and do not posess working technology to upload this, so I have to type it.

Mix of Weak Acids -same process as strong acids, find the major species -find the stronger b/c it is dominant -Ka will be > if concentrations are comparable

__**PERCENT DISSOCIATION**__ = amount dissociated/initial concentration x 100

For weak acids, percent dissociation increases as acid becomes more dilute.

CHEMISTRY JOKE: Q: How did the football cheerleader define hydrophobic on her chemistry exam? A: Fear of utility bills.

3/15 AP CHEM NOTES AND HW REVIEW IN FILE BELOW -Alison Roby

MAURA CARR pd 2

Notes from 3/15

Joe Lutz Period 2 March 18th, 2012

Polyprotic Acids: Sulfuric Acid is SPECIAL: ALSO
 * Always dissociate stepwise
 * First H comes easier than second
 * Ka1 is > than Ka2
 * 1st dissociation is the only one that matters though
 * The second and third dissociation barely affect the Ph so we don't bother with them at all!
 * just know that they happen
 * conjugate base from dissociation 1 becomes the acid for the 2nd dissociation
 * It is strong acid in first step
 * We were supposed to do this problem: Calculate concentration in a 2.0M solution of H2SO4 and calculate concentration in a 2.0E-3M solution of H2SO4
 * if something has 2 more Oxygen than Hydrogen it is a strong acid

_

PJ Succi Period 5 March 18th, 2012

chem joke....

**Annette Ladyzhensky** **Period 5** **March 26, 2012**

**__Notes on Acids & Bases__**







**Chem Joke**

MAURA CARR pd 2 3-26-12 Notes on Acids & Bases



=**March 29, 2012 - Davis Perchk**=

The Common Ion Effect
Ex. HA + H2O <> H30+ + A- 1.0 M .2 M
 * When the salt with the anion of a weak acid/ base is added to that acid/ base
 * It reverses the dissociation of the acid
 * Lowers the percent dissociation of the acid.

When Conjugate is added in, % dissociation changes.

**Buffered Solutions**
HAc + H20 <> H3O+ + Ac- I .5M C -x +x +x E .5M-x x x
 * A solution that resists a change in pH
 * Either a weak acid & its salt or a weak base & its salt.
 * We can make a buffer of any pH by varying the concentrations of these solutions.
 * Calculate the pH of a solution that is .5M

1.8x10^5 = (x^2)/(.5-x) x= .002981 pH = -log(x) = 2.52

I .5M .25M C -x +x +x E .5 - x x .25 +x

1.8x10^5 = (x^2 + .25) / (.5 - x) x = .000036 pH = -log(x) = 4.44 or..... pH = pKa + log([A-]/[HA])

**Adding a Strong Acid or Base**

 * DO THE STOICH FIRST!!!!
 * A strong base will grab protons from the weak acid reducing [HA]o
 * A strong acid will add its protons to the anion of the salt reducing [A-]o
 * THEN DO THE EQUILIBRIUM PROBLEM!!
 * What is the pH of .1L of the previous solution when .01mol of solid NaOH is added?

HAc + NaOH > H20 + NaAc .5M .1M .1M

.4M 0 .1M "pKa = -log(Ka)"

HAc + H20 <> H30+ + Ac- Ka = 1.8x10^-5 .4M .1M

pH = pKa + log([.1]/[.4]) = 4.14

**Buffer Capacity**
DON'T FORGET THAT WE HAVE A WEBASSIGN DUE MONDAY AT 10 PM!!!!!!!
 * The pH of a buffer solution is determined by the ratio [A-]/[HA]
 * As long as this doesn't change much, the pH won't change much
 * Larger concentrations = bigger buffer capacity
 * The best buffers have a ratio [A-]/[HA] = 1
 * This is most resistant to change
 * True when [A-] = [HA]
 * Make the pH = pKa (since log(1) = 0)

March 29th, 2012 Alex Lushchyk
 * __Applying Equilibrium__**



Chem Joke of the Day: A neutron walks into the bar and asks the bartender, "How much for a drink?" The bartender replies, "For you, no charge."

Laura Zimmermann: April 2nd
Here's a picture of the problems we went over in class that were due for homework. (pg856 #11,14,17,20,23,26,29,32,35) _

Adeeba Ghias (Period 5) //Homework Review Problems from page 856 for April 2nd...//
Okey dokey I hope you can read what I have...and I'm sorry that I put it up late!
 * REMINDER: WebAssign due tonight at 10:00 pm! **

Problems # 11, 14, 17, 20, 23



Problems # 26, 29, 35



Problem # 32



CHEM JOKE:

It's not the most exciting joke; I hope you enjoy it!!! :)

Q: What do chemists call a benzene ring with iron atoms replacing the carbon atoms?

A: A ferrous wheel:

code Fe - Fe       /       \ Fe      Fe        \       / Fe - Fe code _

__4/3 Titration notes + Problem 32 from homework.__

__Good evening once more ladies and gentlemen of AP chemistry. This is Christian Diamond, returning to provide you with another exciting installment of Chemistry. Let's begin, shall we?__

__For those of you that care, I've been so kindly provided a picture displaying the rather arduous task of completing problem #32 from the homework.__ __I don't understand it either. Moving right along! It's NOTES TIME!__ __Our lesson today was on the exciting topic of titrations! You SHOULD already know about titrations, but my notes will be thorough nonetheless.__

//**Titrations**// __A titration is when one slowly adds a solution of known concentration to a solution of unknown concentration in the presence of an indicator. An example would be slowly adding .125M NaOH to a solution of HCL and phenolphthalein. Doing this, we can discover the unknown concentration of our second solution! Fun!__ __When the number of moles of our titrant equals that that of the number of moles of our acid or base originally present, we have what is known as the Equivalence Point.__ __On a pH graph (like the ones on the calculator-dealies) the equivalence point would be in the middle of the straightest part of your S curve.__

__Since most of our solutions are just clear, the equivalence point isn't exactly visible. This is where our friend the indicator comes in. We use indicators to find the endpoint.__ __At this point, I appear to have stopped writing in English and switched over to hieroglyphics or some other nonsense. I can't exactly figure out what point I was trying to make, so I'll just write what I have down.__ __-Indicators: weak organic acids that have a different color than their conjugate base.__ __-Endpoint: when the indicator changes color due to the concentration of your conjugate base being larger than that of the acid.__ __The endpoint occurs IMMEDIATELY after the equivalence point.__ __Something to remember, when titrating with a base, choose an indicator with a pKa one less than the pH at the equivalence point. When using an acid, chose and indicator with pKa one HIGHER.__
 * //Indicators//**

I can't draw and there is no way for me to put pictures on here otherwise, so no pictures of titration curves. Sorry about that. However, I can describe them. -Our first example would be a strong acid with a strong base. Our curve looks like an S, and at the equivalence point, our pH is seven. -When we have a weak acid and a strong base, we have the same S, but shifted upwards a tad so that our equivalence point is reached when the pH is higher, like around 8.8 or so. -Our final example is a weak base and a strong acid. Our S is now inverted so as to be upside down, and moved downwards a tad, so that our equivalence point occurs when the pH is slightly lower, at around 5.3.
 * //TItration curves__//**

Some things to remember whilst doing titration calculations. - Always do the stoichiometry first. - Always convert both your acid and base to moles, to determine which is in excess. After this, calculate the pH from the excess. - When working with weak acids or bases, be sure to find the equilibrium before you solve. This is of course, after the stoich, BECAUSE I TOLD YOU TO DO THE STOICH FIRST, WHY DON'T YOU EVER LISTEN TO ME?!?!? - When finding volume, use the total volume. Acid and base. - Finally, when working with both a weak acid and a weak base, make two ICE tables. Also don't complain.

Well, this concludes my section of notes. Don't forget that we have some homework to do over break. Page 858 #48-60 evens. Before I sign out, I will leave you with the customary joke, for your viewing enjoyment.

What do you call a tooth in a glass of water? A one molar solution!!!

and another, because its relevant,

What did one titration say to the other? I'll meet you at the endpoint.

Until next time my friends, this has been Christian Diamond, the greatest blogger that ever was.

Chapter 16: Chemical Kinetics! Gwen Hanley, Pd 5 Sorry this is so late, you guys, hope my notes make sense no joke from me... last time I told a chemistry joke, it got no reaction.

<span style="background-color: #000080; color: #00ff00; font-family: Georgia,serif; font-size: 105px;">KEVIN MILLER

Period 5... 4/16... **RATE LAWS**


**KEY POINTS**


 * Rate law= k[A]^x[B]^y[C]^z
 * Rate law constant = k
 * units for k = [(L/mol)^(overall order -1)/time]
 * ln [A]t/[A]0 = -kt
 * ln [A]t = -kt + ln[A]0

REMEMBER:::: WEBASSIGN DUE TOMORROW AT 10:00 PM.....

MAURA CARR

<span style="background-color: #ff003f; color: #ffffff; line-height: 0px; overflow-x: hidden; overflow-y: hidden;">

April 17 2012, Integrated Rate Laws. Roman Bahdanouski. Homework: p. 716 # 34-38 even, #41-45 odd, # 49,50,52,58. Due Thursday.

<span style="background-color: #c0c0c0; color: #404040; display: block; font-family: Verdana,Geneva,sans-serif; text-align: center;">**Electro Chem** <span style="background-color: #c0c0c0; color: #404040; display: block; font-family: Verdana,Geneva,sans-serif; text-align: center;">**Maria Jose Alanis**

Electromotive Force (EMF)
<span style="font-family: Verdana,Geneva,sans-serif; font-size: 130%;">*Electrons only spontaneously flow one way in redox reactions, from higher to lower potential

<span style="font-family: Verdana,Geneva,sans-serif; font-size: 130%;">The potential difference betwen the anode and the cathode in the cell is called the EMF <span style="font-family: Verdana,Geneva,sans-serif; font-size: 130%;">It is also called the cell potential and designated Ecell

<span style="font-family: Verdana,Geneva,sans-serif; font-size: 130%;">Cell Potential OR Ecell
<span style="font-family: Verdana,Geneva,sans-serif; font-size: 130%;">Cell potential is measured in volts (V)

<span style="font-family: Verdana,Geneva,sans-serif; font-size: 130%;">1V = 1J/C

<span style="font-family: Verdana,Geneva,sans-serif; font-size: 130%;">V: Volts <span style="font-family: Verdana,Geneva,sans-serif; font-size: 130%;">J: Joules <span style="font-family: Verdana,Geneva,sans-serif; font-size: 130%;">C: Coulombs

<span style="font-family: Verdana,Geneva,sans-serif; font-size: 130%;">Ecell = Ereduction (cathode) - Ereduction (anode)

<span style="font-family: Verdana,Geneva,sans-serif; font-size: 130%;">*if the Ecell is positive it's spontaneous (THIS IS ALWAYS TRUE)

<span style="font-family: Verdana,Geneva,sans-serif; font-size: 150%;">Remeber Delta G?
<span style="font-family: Verdana,Geneva,sans-serif; font-size: 130%;">^G for a redox reaction can be found using the following equation

<span style="font-family: Verdana,Geneva,sans-serif; font-size: 130%;">^G (delta G) = -nFE <span style="font-family: Verdana,Geneva,sans-serif; font-size: 130%;">*under standard temperature and pressure

<span style="font-family: Verdana,Geneva,sans-serif; font-size: 130%;">n: the number of mols of electrons transferred <span style="font-family: Verdana,Geneva,sans-serif; font-size: 130%;">F: a constant (96,485 c/mol)



<span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">Electrolytic Cell
<span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">-Running a galvanic cell (or voltaic cell) backwards <span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">-Putting a voltage bigger than the potential and reverse the direction of the redox reaction


 * <span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">Voltaic **

<span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">Anode --> Cathode

**<span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">Electrolytic **
<span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">Cathode <-- Anode

<span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">Caluculating Planting
<span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">-Measure current I (in amperes) <span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">- 1amp = 1 coulomb of charge per second <span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">- Q = I x T.... &.......Q/nF= mols of metal

<span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">Q: charge in coulombs <span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">I: current <span style="font-family: Verdana,Geneva,sans-serif; font-size: 120%;">T: time