COMPLETE 60 QUESTIONS WITH DETAILED VERIFIED ANSWERS
ALREADY GRADED A+
***ANSWERS IN BOLD***
1. C: Where is the hydrophilic (attracted to water) region of the molecule?
f f f f f f f f f f f
(A) Region 1 f
(B) Region 2 f
(C) Region 3 f
(D) The three regions are equally hydrophilic
f f f f f
2. C: Which molecule is most soluble in water?
f f f f f f f
1 f/
,3. D: A solution of NaCl in water has a concentration of 20.5% by mass. What is the
f f f f f f f f f f f f f f f f
f molal concentration of the solution?
f f f f
Molar Mass NaCl = 58.44
f f f f
f g/mol (A) 0.205 m f f f
(B) 0.258 m
f f
(C) 3.51 mf f
(D) 4.41 mf f
4. B: What is the mole fraction of water in 200 g of 89% (by mass) ethanol, C2H5OH?
f f f f f f f f f f f f f f f f
Molar Mass C2H3OH = 46f f f f
f g/mol (A) 0.11 f f
(B) 0.24 f
(C) 0.32 f
(D) 0.76 f
5. D: A mixture of 100 g of K2Cr2O7 and 200 g of water is stirred at 60 degrees C
f f f f f f f f f f f f f f f f f f
f until no more of the salt dissolves. The resulting solution is poured off into a
f f f f f f f f f f f f f f
on during f
f separate beaker, leaving the undissolved solid behind. The solution is now colled
f f f f f f f f f f f
f to 20 degrees C. What mass of K2Cr2O7 crystallizes from the soluti
f f f f f f f f f f f
2 f/
,cooling?
(A) 9 g f
(B) 18 g f
(C) 31 g f
(D) 62 g f
6. A: Carbonated beverages have a fizz because of gas dissolved in the solution.
f f f f f f f f f f f f
f What increases the concentration of gas in a solution?
f f f f f f f f
(A) cooling the solution
f f
(B) heating the solution
f f
3 f/
, (C) increasing the volume of solution f f f f
(D) decreasing the volume of solution f f f f
7. D: When 100 g of an unknown compound was dissolved in 1.00 kg of water, the
f f f f f f f f f f f f f f f
f freezing point was lowered by 6.36 degrees C. What is the identity of this unknown
f f f f f f f f f f f f f f
f compound?
Kf for water = 1.86 degrees C/m
f f f f f f
(A) CsCl
(B) KCl
(C) LiF
(D) NaCl
8. A: Which 0.1 molal aqueous solution will have the lowest freezing point?
f f f f f f f f f f f
(A) Al(NO3)3
(B) CaCl2
(C) C2H5OH
(D) NaCl
4 f/