<p>the Al3+ ion forms complexes with water, which are acidic since (this is kind of a stretch) e- density is more or less removed from the bonded H on the O that it floats away.</p>
<p>also, the S2- is a stronger base than water</p>
<p>by the way, the crazy two site is a good find thanks</p>
<p>What volume of water should be added to 0.40 L of 6.0 M H2SO4 solution to produce a solution that is 2.0 M H2SO4?
A. 0.40 L
B. 0.80 L
C. 1.2 L
D. 1.6 L
E. 2.4 L </p>
<p>Why is this C and not B?</p>
<p>MV=MV
(.4)(6.0)=(2.0)(x)
2.4=2x
2.4/2=x
1.2=x, therefore the answer is C</p>
<p>guptasaintx - DankStarbursts' math is right, but you are correct that the answer is B. The new total volume is 1.2, but the amount of water added is approximately 0.8. Not sure where you got the question from, but the answer key is wrong.</p>
<p><a href="http://www.adriandingleschemistrypages.com/apquiz.htm%5B/url%5D">http://www.adriandingleschemistrypages.com/apquiz.htm</a>
^ that link is not working for me...</p>
<p>thanks. i did what dankstarbursts did, but i agree. i think the question's answer key is not correct. thx</p>
<p>I've heard Barrons has good AP Chem prep. I'm using their prep book right now.</p>
<p>Also, does Organic Chem play a big role on the test?</p>
<p>I'm pretty certain organic chem is almost never on it.
Maybe there will be like 1 or 2 questions, I don't know.</p>
<p>There are certain types of problems where organic sometimes comes up.
Ex 1: Simple organic naming shows up in FR Question 4 where you have to write net ionic equations. "Methanol is burned in air."</p>
<p>Ex 2: Organic molecules are often used as examples in questions about lewis dot structures, hybridization, sigma and pi bonds, etc, and they are often examples in questions about interparticle forces (LDF, HBonding, Dipole-Dipole). These types of questions often don't require actual organic knowledge, but familiarity with organic structures may make you more comfortable with the question.</p>
<p>Ex 3: The 1984, 89, 94, 99 and 2002 released exams had exactly one organic multiple choice question each. 3 questions were on recognizing structural isomers, one was on the properties of structural isomers, and one was on recognizing optical isomers.</p>
<p>1989 Question 31
The structural isomers C2H5OH and CH3OCH3 would be expected to have the same values for which of the following? (Assume ideal behavior)
(A) Gaseous densities at the same temperature and pressure
(B) Vapor pressures at the same temperature
(C) Boiling points
(D) Melting points
(E) Heats of vaporization</p>
<p>Is it A?</p>
<p>Thats a pretty hard question but I am thinking its A because the rest have to do with breaking bonds and bonding is the only thing different about structural isomers.</p>
<p>I think it's A because they both have the same molar mass. Therefore, they would be 22.4 L per mole of gas, would have to have the same volume and mass, and therefore density. Some of the others definately don't make since because C2H5OH exhibits a fairly large degree of hydrogen bonding.</p>
<p>A, They are structural isomers which means they have the same formula (composition) and therefore the same molar mass. If the containers have equal volume. There is no reason for them not to have the same density </p>
<p>QUESTION 1. Which of the following pairs have the same atomic geometry?</p>
<p>(A) BF3 and NH3
(B) Carbonate ion and BF3
(C) NH3 and PF5
(D) PF5 and SF6
(E) H2O and NH3 </p>
<p>No Clue Whats wrong with the link. You can reach the page from here :
Steven</a> Haderlie's AP Chemistry Resource Page</p>
<p>i have the answers to the 1999 mc ;-)</p>
<p>1) c 2) e 3) b 4) a 5) d 6) a 7) c 8) e 9) c 10) e 11) a 12) b 13) a 14) b 15) d 16) c 17) e 18) a 19) c 20) b 21) b 22) e 23) e 24) d 25) c 26) c 27) a 28) b 29) e 30) d 31) c 32) d 33) c 34) a 35) c 36) b 37) c 38) b 39) c 40) d 41) e 42) c 43) d 44) c 45) d 46) c 47) c 48) b 49) e 50) d 51) e 52) b 53) a 54) b 55) d 56) a 57) a 58) c 59) c 60) a 61) e 62) a 63) b 64) a 65) a 66) a 67) e 68) d 69) c 70) a 71) b 72) b 73) d 74) a 75) d </p>
<p>sorry if it's kind of hard to read</p>
<p>id say (a) BF3 and NH3</p>
<p>Doesn't help much w/o the test questions </p>
<p>FASTEST way to Review STAT (include Review books) </p>
<p>I have Gov on Mon.
APUSH on Fri.
CHEM on Tues</p>
<p>id say (B) Carbonate ion and BF3</p>
<p>It's (E) H2O and NH3</p>
<p>Remember your lone pairs for electron geometry.</p>
<p>Actually, it is B (carbonate and BF3). The wording is very subtle; the question asks for atomic geometry (though the term "molecular geometry" is usually used), not electron geometry. So although H2O and NH3 both have the same electron geometry (tetrahedral), the molecular geometry of H2O is bent, while NH3's is trigonal pyramidal.</p>
<p>Carbonate and BF3 both have the same geometry (both electron and molecular); both are trigonal planar.</p>
<p>
[QUOTE]
Actually, it is B (carbonate and BF3). The wording is very subtle; the question asks for atomic geometry (though the term "molecular geometry" is usually used), not electron geometry. So although H2O and NH3 both have the same electron geometry (tetrahedral), the molecular geometry of H2O is bent, while NH3's is trigonal pyramidal.</p>
<p>Carbonate and BF3 both have the same geometry (both electron and molecular); both are trigonal planar.
[/QUOTE]
</p>
<p>So "atomic geometry"=molecular geometry. Thanks for the heads up!</p>