Form Code X
NAME________________________________________
CHM 2045, Fall 2016 Exam 1
Final Packet Instructions: Do your best and don’t be anxious. Read the question, re-read the question,
write down all given or valuable information, and write down what you want to find. As on all graded
events, the loving of moles applies.
1. A solution of sucrose in water is 68.5% sucrose by mass and has a density of 1.59 g/mL. What
mass of sucrose, in grams, is contained in 4.00 L of solution?
1) 3.5x103 g sucrose 2) 1.1x103 g sucrose 3) 3.5 g sucrose 4) 4.4x103 g sucrose 5) 4.5 g sucrose
2. The compound (X) contains 49.48 % carbon, 5.191 % hydrogen, 28.87 % nitrogen, and
16.48% oxygen by mass. Additionally, X’s molecular weight lies between the domain of
Compound Y’s MW and Compound Z’s MW. If MWY = 188 g/mol and
MWZ = 200 g/mol. Which of the answers shows the molecular formula and empirical formula
of the compound respectively.
1) C8H10N4O2, C4H5N2O
2) C8H10N4O2 , C8H10N4O2
3) C8H8N3O3, C8H10N4O2
4) C10H7N5O2 , C8H10N2O
5) C8H10N2O, C8H10N2O
3. The radioactive 60Co isotope has which Z, neutron number, and A (respectively)?
1) 33, 60, 27
2) 27, 33, 60
3) 60, 27, 33
4) 20, 81, 35 5) 35, 27, 11
4. If 1.951 g BaCl2·xH2O yields 1.864 g of anhydrous BaSO4 (136.14 g/mol) after treatment with
excess sulfuric acid, what is the value of x in the formula of BaCl2·xH2O? (round to nearest
whole number)
1) one
2) two
3) three
4) four
5) five
5. If a sheet of aluminum foil (d = 2.70 g/cm3) weighs 10.36 lbs and is 0.01222 mm thick, the
surface area of the foil is closest to…?
(1) 4.01*10-5 ft2 (2) 13.9 ft2 (3) 0.06177 ft2 (4) 1540 ft2
(5) 825 ft2
6. If 12.00 g of element G reacts with 18.00 g of element M to produce 23.00 g of a compound
with the formula G3M4, and the atomic mass of M is 160.0 amu, what is the atomic mass of G?
1) 60.5 amu
2) 122.0 amu 3) 72.0 amu
4) 89.5 amu
5) 142.2 amu
7.
Both Mg3N2 (100.9 g/mol) and Mg(OH)2 (58.3 g/mol) can be converted to MgO (40.3 g/mol) by
appropriate means. If a 2.00 g mixture of these two compounds is converted, and 1.50 g of
MgO is obtained, what is the approximate mass percent of Mg3N2 in the mixture?
(1) 11.5% (2) 20% (3) 50% (4) 10% (5) 96%
8. Which of the following ionic compounds/names are true?
A) NH4Cl (Ammonium Chloride) B) Fe2O3 (Iron (III) Oxide)
1) A, B, and C
2) A only
3) A and B only
C) NH3 (Ammonia)
4) B only
5) C only
9. Which of the following is closest to the mass of chromium in 1.064 g Chromium (III) Oxide?
1) 0.342 g 2) 0.727 g 3) 0.682 g 4) 1.064 g 5) 1.042 g
10. If volumes are additive and 80.0 mL of 0.40 M sodium chloride is mixed with 120 mL of a
calcium chloride solution to give a new solution in which [Cl-1] is 0.52 M, what is the
concentration of the calcium chloride used to make the new solution?
(1) 0.60 M
(2) 0.30 M
(3) 0.072 M
(4) 0.036 M
(5) 0.52 M
11. Given the reaction: 3 H2S + 2 FeCl3  Fe2S3 + 6 HCl
We have 50.0 g of FeCl3 reacts with 52.0 g of H2S. How much of the excess reactant is left over
after reaction?
1) 15.758g
2) 36.24g
3) 105.98g
4) 0.462g
5) 52.0g
12. The concentration of LiOH is 0.50 M. If 25 mL of LiOH is needed to titrate 40 mL of HNO3
(nitric acid) what is the concentraiton of HNO3?
1) 0.03125 M HNO3 2) 0.8 M HNO3 3) 0.3125 M HNO3 4) 0.08 M HNO3 5) 1.00 M HNO3
13. Select the false statement below:
(1) Pb2+(aq) + 2I− (aq) → PbI2(s) is a precipitation reaction but is not a redox reaction
(2) CH4(g) + 2O2(g) → CO2(g) + 2H2O(g) is a combustion reaction and a redox reaction
(3) Ca(s) + F2(g) → CaF2(s) is a precipitation reaction and a redox reaction
(4) HNO3(aq) + KOH(aq) → H2O(l) + KNO3(aq) is an acid-base reaction but is not a redox
reaction
(5) H2SO4(aq) + Ba(OH)2(aq) → 2H2O(l) + BaSO4(s) is a precipitation reaction and an acidbase reaction
14. In which of the following equations are the base and conjugate base (proposed bases are
underlined) incorrectly labeled?
(1) HCl + H2O  Cl- + H3O +
(2) H2PO4 - + H2O  H3PO4 + OH(3) CN- + H2O  HCN + OH(4) CH3COOH + H2O  CH3COO- + H3O +
(5) HCO3 - + H2O  H2CO3 + OH-
15. A 12.22g mixture of copper(II) sulfate pentahydrate and magnesium sulfate heptahydrate is
created. The mixture of hydrates is placed into an oven and heated at 550o C for two hours.
After two hours, the water has evaporated and the mixture yields 7.298g of anhydrous salts.
Find the percent by mass of the magnesium sulfate heptahydrate in the original mixture before
the heating.
1) 72.32%
2) 27.67%
3) 3.38%
7.298%
5) 48.8%
16. An acid solution is 0.120M in HCl & 0.210M in H2SO4 is created for a titration experiment in
the course CHM3120. What volume of a 0.150M KOH solution would have to be added to
550.0 mL of the acidic solution to neutralize completely all of the acids?
1) 0.44 L 2) 1.54 L
3) 0.3125 L 4) 0.08 L
5) 1.98 L
GOOD LUCK AND SMILE ON THE EXAM!
-Broward Teaching Center