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Ah crud.. I just typed alot and it all got erased.. Well basically I am going to be taking AP Chem this year. I've been doing my summer assignments lately.. and it's been really difficult.. So if any of you people (like jason or someone) who took ap chemistry could just give me a hand with these problems i'd really appericiate it.. I am not trying to get you guys to do my hw or anything. Believe me I have been trying, and I just want some reassurance, comments, and explanations for the ones I am not too clear with. Well here are the problems. If you don't have the time to look over all of them just briefly look at these numbers ( 1, )

1.Which one of the following is true about an individual atom?
a. Indiv. atom should be considered as solid
b. " " liquid
c. " " gas
d. The sate of the atom depends on which element it is.
e. An indiv. atom can not be considered as solid liquid or gas
Justify your choice, and for the choices you did not pick, explain what is wrong with them.

I personally think it's d... again let me know..

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:11 pm: Edit

btw.. i am going to be posting questions one by one.. bec. i just had typed up like 8 questions.. and my comp got f'd up..

2. Several compounds containing only sulfur and fluorine are known. Three of them have the following compositions:
i. 1.188g of F for every 1.00g of S
ii.2.375g " "
iii. 3.563g " "

How do these data illustrate the law of multiple proportion.

Well I had found a relationship between ii over i, which is 2 over 1 and iii over i which is 3 over 1. I just need a clearer understand of this prob.

By Jason817 (Jason817) on Tuesday, August 12, 2003 - 12:12 pm: Edit

It's D as you said. Some atoms are solids (i.e. calcium), some are liquids (bromine), some are gases (chlorine)

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:12 pm: Edit

PLeasssssssseee look at this one!!!

3. What is the symbol of an ion with 16 protons, 18 neutrons, and 18 electrons? What is the symbol for an ion that has 16 protons, 16 neutrons, and 18 electrons?

By Fairyofwind (Fairyofwind) on Tuesday, August 12, 2003 - 12:12 pm: Edit

It is E. An atom cannot be in any state, because the state of matter depends on interparticle attractions, which gives solids, liquids, and gases their respective properties.

Jason: The element can have a state of matter at room temperature, but a single atom does not.

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:14 pm: Edit

4. Would you expect each of the following atoms to gain or lose electrongs when forming ions? What ion is the most likely in each case?
a. Na My answers: Lose (most likely)
b. Sr Lose
c. Ba Lose
d. I Gain
e. Al Lose
f. S Gain (most likely)

I think I got this right.. whether i did or not.. please provide with a clear exlpanation

By Fairyofwind (Fairyofwind) on Tuesday, August 12, 2003 - 12:15 pm: Edit

3. S (16) (34) (2-), S (16) (32) (2-)

By Fairyofwind (Fairyofwind) on Tuesday, August 12, 2003 - 12:16 pm: Edit

For non transition elements, Groups 1, 2, 13 lose 1-3 electrons when forming ions, Groups 15, 16, 17 gain 1-3 electrons when forming ions. So you are right.

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:19 pm: Edit

5. Name each of the following compounds: (I=i just to get rid of the confusion)
a. Cu I
b. Cu I2
c. Co I2
d. Na2 CO3
e. Na H CO3
f. S4 N4
g. S F6
h. Na O CL
i. Ba Cr O4
j. NH4 NO3

Again my answers
Copper Iodide
Copper(ii)iodide
Cobalt(ii)iodide
Sodium Carbonate
Sodium Bicarbonate
Tetrasulfur tetranitride
Sulfur hexaflouride
Sodium Hypochlorite
Barium Chromate
Ammonium Nitrate

Very unsure about writing out compounds.. again suggestions, explanations would be appericiated

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:19 pm: Edit

fairy of wind thx for replying.. i got like 3 more questions to go :d

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:20 pm: Edit

uh o.. and jason too :d

By Fairyofwind (Fairyofwind) on Tuesday, August 12, 2003 - 12:21 pm: Edit

Copper (I) iodide and sodium hydrogen carbonate (bicarbonate is not standard). Others look okay.

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:23 pm: Edit

Write the forumla for each of the followign compounds:
a. cesium bromide
b. barium sulfate
c. ammonium chloride
d. chlorine monoxide
e. silicon tetrachloride
f. Chlroine trifluoride
g. Beryllium oxide
h. magnesium fluoride

me answers:
a. CsBr
b. BaS
c. NH4 Cl
d. Cl O
e. SiCl4
f. Cl F3
g. Be O
h. Mg F2

By Fairyofwind (Fairyofwind) on Tuesday, August 12, 2003 - 12:24 pm: Edit

b. Ba SO4 Others are correct

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:27 pm: Edit

The formulas and common names for several substances are given below. Give the systematic names for these substances.

a.sugar of lead Pb(C2 H3 O2)2
b. Blue vitrol Cu SO4
c. Quicklime Ca O
d. Epsom salts Mg S O4
e. Milk of magnesia Mg (OH)2
f. Gypsum Ca SO4
g. Laughing Gas N2 O

me answers:
acetic acid
copper(ii)sulfate
calcium oxide
magnesium sulfate
magnesium hydroxide
calcium sulfate
dinitrogen monoxide

By Fairyofwind (Fairyofwind) on Tuesday, August 12, 2003 - 12:28 pm: Edit

Lead (II) acetate

Others are correct

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:31 pm: Edit

wow fairy thx you for all ur help.. i got like 2 more to go..

Totally clueless on this one.. sorta..

another mulitiple proportion one..

Two elements R and Q combine to form two binary compounds. in the first compound, 14.0 g of R combines with 3.00 g of Q. in the second compound, 7.00 g of R combines with 4.50 g of Q. Show that these data are in accord with the law of multiple proportions. If the formula of the second compound is RQ, what is the formula of the first compound.

By Fairyofwind (Fairyofwind) on Tuesday, August 12, 2003 - 12:34 pm: Edit

The second compound is RQ. Which means they combine in the proportions 7.00 g R/4.50 g Q. So the first compound is R 2 Q (2/3), multiplying through by 3, gets R6Q2, simplifies to R3Q as the empirical formula. Note that they are whole numbers--law of multiple proportions.

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:36 pm: Edit

This one is the last one.. I haven't attempted this one yet.. please post the answer so i can refer to it later when i solve by myself..

CH4 is a typical covalent compound while CsCl is a typical ionic Compound

a. list what properties a typical covalent compound has and explain clearely why being covalent can give it each property

b. List what properties a typical ionic compound has and explain clearely why for each prop.

this one seems pretty long and tidious.. just give me a brief answer u can so i can look back at it to see if i got it right.. btw.. how did u become so amazing at chemistry? did you pracitce alot? It just amazes me taht someone has all the polyatomic ions memorized and stuff.. well seriously thx for all your help.. btw.. is there antyhing u recommend me to do for this ap course? well again thx you sooo much fairy

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:37 pm: Edit

lol wow 800 sat 2 chem.. go figure :D.. I am gonna try hard to get there and to get 5 on the ap test

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:41 pm: Edit

wait for RQ question.. i am not sorta getting.. could u explain it more clearly if that is possible?

By Fairyofwind (Fairyofwind) on Tuesday, August 12, 2003 - 12:42 pm: Edit

Covalent compound:

Electrons shared.
Can be found as any state at room temperature.
Nonmetal--nonmetal
Do not conduct electric current

Ionic compound:
Electrons transferred.
High melting/boiling point--because of the attraction of oppositely charged ions--electrostatic forces.
Also why usually solids at room temperature.
Conductor of electricity in molten state/aqueous solution--due to ions, again
Soluble in water--like dissolves like (water is a polar substance)
Metal--nonmetal

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:42 pm: Edit

so the final answer is 3RQ?

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:44 pm: Edit

btw. i am amazed i got alot of these right.. maybe chem wont be too bad after all

By Fairyofwind (Fairyofwind) on Tuesday, August 12, 2003 - 12:45 pm: Edit

Basically 7.00 g R and 4.50 g Q form the compound RQ because the number of moles of 7.00 g R/number of moles of 4.50 g Q=1. The law of multiple proportions states that elements combine in whole number ratios. Say 7.00 g R is x moles. Then 14.00 g R is 2x moles. Similarly, 4.50 g Q is also x moles. Then 3.00 g Q is (2/3)x moles. So the other compound is R(2x)Q(2/3)x, But cancelling out the x and multiplying by (3/2) simplifies this to R3Q. Notice that in this compound, the # moles R: # moles Q is 3:1, which is a whole number ratio satisfying the law of multiple proportions.

By Serene (Serene) on Tuesday, August 12, 2003 - 12:45 pm: Edit

I didn't see any iron acetate...? fairy you meant lead right?

By Fairyofwind (Fairyofwind) on Tuesday, August 12, 2003 - 12:47 pm: Edit

Oops yes Lead (II) acetate hehe

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:47 pm: Edit

yeah i think that's what fairy meant

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:48 pm: Edit

hey what about that other multiple proportion question way up there.. btw.. am i gonna get in trouble for posting so much :/

By Serene (Serene) on Tuesday, August 12, 2003 - 12:50 pm: Edit

the second problem? well if the first ratio is
x:y and x and y both being integers, then the next two are
2x:y
3x:y

and 2x and 3x are also integers...

By Fairyofwind (Fairyofwind) on Tuesday, August 12, 2003 - 12:51 pm: Edit

1.188 g F/1.00 g S = 0.0625 mol F/0.0313 mol S=2.

So the first one satisfies the law of multiple proportions. Now, since 2.375 g = 1.188 g * 2 and 3.563 g = 1.188g * 3, the others must also satisfy the law of multiple proportions.

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:52 pm: Edit

k that's what i thought.. thx serene and fairy

now what do you guys recommend i do for this somewhat dreaded chemistry course :D? like any tips,hints, etc

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:53 pm: Edit

btw is this like the easiests of the easiest on the sat2 and ap chem?

By Fairyofwind (Fairyofwind) on Tuesday, August 12, 2003 - 12:54 pm: Edit

Honestly. I hated chemistry. But I hate physics more, so it's all good. I am actually taking AP chemistry next year; I also have a lot of this crap summer work to do. I'd just suggest doing a lot of problems to get used to this stuff.

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 12:56 pm: Edit

lol k thx.. i don't see how anyone can seriously thoroughly enjoy chemistry.. again thx you,serene, and jason for all the help.. nearly saved my life

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 01:01 pm: Edit

wiat for no5.. why would it be copper (i)iodide instead of copper iodide?

By Fairyofwind (Fairyofwind) on Tuesday, August 12, 2003 - 01:02 pm: Edit

Copper, can form more than one type of ion, so just as you write Copper (II) iodide for CuI2, when it's CuI, you write Copper (I) iodide.

By Joel_Set (Joel_Set) on Tuesday, August 12, 2003 - 01:05 pm: Edit

k gotcha.. gotta go to bed now.. it's like 2 int he monring here (*can't u tell from my spelling :D).. cya

By Spacechic20 (Spacechic20) on Thursday, August 14, 2003 - 12:50 am: Edit

here are a few words of ap chem wisdom! (well, not really.) i took ap chem this past yr with a WEAK background in honors chem. we had no summer assignments or anything, never any homework, i couldnt find my ap chem textbookm from august-may, and my teacher frequently taight for only the first half of class and the other half of the class we just talked about american idol, our weekends, etc. i got a 5. here's the thing. you must know your net ionic equations. i feel like they're the most undertaught (is that a word) part of the test and its worth 15%! they can raise ur whole ap score. also, i think that this yr's required question will be on gas equilibrium. my second choice is Ksp, but gas equilibrium is fairly simple, so if u can get that i think you'll be ok. as for the multiple choice, it is overwhelming and it does test you on everything, but getting 50/75 will get you a 5. just think positive, there's no reason that you can't figure a question out, and you'll be fine.
by the way, princeton review does a GREAT job with chem. it's the only review book i've ever used for an AP.

By Y17k (Y17k) on Thursday, August 14, 2003 - 06:44 am: Edit

wow chemistry is easy stuff ^^

at least im prepared for somthing

By Jason817 (Jason817) on Thursday, August 14, 2003 - 11:05 am: Edit

It's harder than that. Spacechic must be really really smart

By Joel_Set (Joel_Set) on Thursday, August 14, 2003 - 11:36 pm: Edit

lol spacechic thx for the encouragement