this is the test
http://www.forestridge.org/faculty/.../ap_mc_1999.htm

and these are the answers
http://www.forestridge.org/faculty/...SWSERS_1999.htm

would anybody who has ANY knowledge in ap chem help me try to figure out why these are the answers? like a short explanation thanks you so much in advance

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i hate you... if i had seen this one day earlier i would have gotten 100% on todays' test which was that exact multiple choice...
gawd damn

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aight, i'll try to help (i'm taking chem, cant take AP chem till next year) but i like helping ppl (cause i'd need it sometime)

1. Ionization energy is the formation of / separation into ions by heat, electrical discharge, radiation, or chemical reaction.

2. Lattice energy has to do with ions or molecules in a crystalline solid. The question involves trasitions with ionic solids...so i guess it's the answer? (Sorry but i'm trying my best here)

3. Free energy, well all i know is that you find this by using this formula(i think):
Enthalpy - (absolute temp)(Entropy)
Is free energy the same as potential energy? well i guess free energy is the amout available so it just fits.

4. oh snap! I would have put Kinetic energy for this. But now i think that Kinetic energy is released so it isn't required. The answer was activation energy, which would be the amount added heat that was required

Aight, that's all i can figure from these first 4 questions. I guess you'd need the definitions of the 5 types of energy.

It's late i gotta go sleep i'll try to help some more later.

c ya

Last edited by Alchemist on 04-18-2002 at 06:25 PM

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omg thankies ^_^

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some more info

ok you're welcome (post a message if you've already got it, you took the test already, or i'm not really helping that much etc.)

The second part # 5-8 deals with the orbital model of an atom

If an energy level is skipped (atom 1) then the atom is excited. at ground state the electrons would fill the lower energy levels first.

Atoms are unreactive if all principle energy fields are filled because they are stable and noble gasish. uh the valence electrons for the atoms given are (I think):
a. 1
b. 2
c. 4
d. 6
e. I don't know about e.
The valence electrons are extra electrons. (filled layers are 8)

the Acids in # 9-12 deal with ph. I think it's in the reference table but i'm not sure

Sorry if i can't help you that much.
If you need help is specific parts, post the questions or section of the test. I'll try to help some more and hopefully others will try to help also.

Last edited by Alchemist on 04-19-2002 at 05:26 PM

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no no you're helping sooooo much ^_^ this is due by whenever i can finish it, i'm gonna try to finish it by monday though

i got some of the explanations the ones i REALLY need are:

9-20, 26, 30, 33, 36, 37, 40, 42, 43, 46, 47, 53, 55, 56, 59, 60, 61, 63-75

if you could help me with these problems (not just alchemist but ANYONE) i would be forever grateful......thank you alchemist so far ^_^ feel free to post some more you are doing me a REALLY good favore

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ok

26.
. . . .C10H12O4S(s) + . . O2(g) ---> . . . CO2(g) + . . . SO2(g) + . . . H2O(g)

All you're doing is balancing the equation. You plug in coefficients so that all of the elements on each side are equal. to find how many atoms of an element there are on a side you multiply the coefficient and the subscript # that is after the element. ex: 2cO2 has 4 oxygen atoms and 2 Carbon atoms.

33. I don't know if this is right but: you multiply the number of moles (.10) of NaCl by 1 because of the 1 atom of chlorine, and add that to .20 which is the product of .10 moles of CaCl2 and the 2 atoms of Chlorine in it. it gives you .30 moles.

37. I think you use the reference table for this (i'm not sure, but i think it might be there)

40. Dipole attaction is when a polar molecule with a positive and negative end is near another polar molecule with a positive and negative end then the opposite ends attract and form a bond.

42. this question is similar to # 26 so you just do the same thing

43. Molarity is moles of solute per liter of solution. you can find the moles by using the grams and 1.0 molal solution. So all you need is the liters. since liters are used to measure volume, the answer is choice D.

"Need Backup"
I got upto question 64 and i'm not able to figure out any of the ones i didn't post. It's also kinda late now. Oh well, see you later.

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OMG WOW!!! you did SUCH a good job i love you!!!! thank you thank you!!!

remember everyone else!! other people can still help me too!! i don't wanna put all the pressure on alchemist

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oh thanks,

I'm kinda busy today and I'm not allowed to go on the comp during weekdays (I got a 70 in english :sad: )

oh well, i hope you finish

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Those are about the easiest problems I ever seen...
All you do is to cram and memorize all the different kinds of energies inside your head.. and youre all set for an AP CHEM exam!

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quote:

---

Originally posted by loser
i hate you... if i had seen this one day earlier i would have gotten 100% on todays' test which was that exact multiple choice...
gawd damn

---

seriously.. the 1999 exam was our in class final.
oh well, i didn't do bad on it, hehe.

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to GinaDaQueen:
the questions on the test aren't that bad. even the short answers part b&c were really easy! well if the test isn't already over with, u can IM me on aim-- iiasnprncssii.

btw, can u skip some problems that u don't know? i ended up skipping around 15-20

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thanks everyone i already finished it!!

hehe i failed the ap chem exam cuz the teacher never actually TAUGHT us......he just gave us notes....oh wellz

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oh no! If your teacher isn't good then the class is much harder.

My math teacher isn't that good and lots of ppl fail exams.

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ooh same in my math class...but i'm still passing cuz i'm good in math hehe

yeah we (chem students) all left the free fresponse questions blank and just sat there for an hour not doing anything

eh, we failed.........

but we get 100s on all of the chem tests cuz he always makes it open book

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woah.. i wish my teacher did that =p
ah well im kinda curious about what i got on the actual ap.. not that i'm worried or anything, im not planning on becoming anything that is related to chem.. oy i got so sick of it.. lol

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ewww, chemistry. i'm so glad that class is over with already. and to think i was thinking about majoring in chemistry........

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I liked chem, i'm sorry i couldn't help you any more. That question about the avalable energy being free energy, all my friends I showed it to said it was potential energy because we didn't learn that so specifically.

a lot of ppl in my grade(sophomore) are going to take AP physics and AP Chem and they think it's gonna be easy as hell. haha, i'm gonna laugh at them just like i did when they took seq 3H

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