Download CHEMISTRY: Practice Spring Final

Name: _____________________________ Per: ____
CHEMISTRY: Practice Spring Final
MRS. WARD
Note: Do not JUST study this practice exam; it does not contain every topic that may appear on your final
exam. Be sure to look at your review guide to see a list of topics you are responsible for. Also, this practice test
is broken up by topic; your final exam will not be.
CHEMICAL REACTIONS
1) Classify the following reaction: 3CuSO4 + 2Al  Al2(SO4)3 + 3Cu
A) synthesis
C) double replacement
B) single replacement
D) decomposition
2) Classify the following reaction: Cu(OH)2  CuO + H2O
A) synthesis
C) double replacement
B) single replacement
D) decomposition
3) What is the balanced equation when aluminum reacts with copper II sulfate?
A) Al + Cu2S  Al2S + Cu
C) Al + CuSO4  AlSO4 + Cu
B) 2Al + 3CuSO4  Al2(SO4)3 + 3Cu
D) 2Al + Cu2SO4  Al2SO4 + 2Cu
4) In a combustion reaction, one of the reactions is
A) hydrogen
C) oxygen
B) nitrogen
D) a metal
5) Balance the following equation: Fe + O2  Fe2O3
A) 4, 3, 2
C) 1, 2, 3
B) 2, 1, 1
D) 2, 3, 1
6) Which one of the following metals could produce zinc metal, if heated with zinc oxide?
A) Aluminum
B) Copper
C) Iron
D) Silver
7) A compound contains 6.0 g of cabon and 1.0 g of hydrogen. The percent composition of the compound is:
A) 14 % hydrogen and 86 % carbon
B) 86 % hydrogen and 14 % carbon
C) 17 % hydrogen and 83 % carbon
D) 83 % hydrogen and 17 % carbon
STOICHIOMETRY
8) The molecular formula for aspirin is C9H8O4. What is its empirical formula?
A) C9H8O4
B) C3H2O2
C) CHO
D) none of the above
9) What is the empirical formula for a compound that is 31.9% potassium, 28.9% chlorine, and 39.2% oxygen?
A) KClO2
B) KClO3
C) K2Cl2O3
D) K2Cl2O5
10) A compounds empirical formula is NO2. If the molar mass is 92 g/mol, what is its molecular formula?
A) NO
B) N2O2
C) NO2
D) N2O4
11) What is the number of moles in 500 L of He gas at STP?
A) 0.05 mol
B) 0.2 mol
12) Given the reaction: CH4 + 2 O2
1 mole of CH4?
A) 2 moles
C2H4 + 3 O2
B) 2 atoms
C) 22 mol
D) 90 mol
CO2 + 2 H2O, what amount of oxygen is needed to completely react with
C) 2 grams
D) 2 molecules
2 CO2 + 2 H2O
13) If 6.0 mol of CO2 are produced, how many moles of O2 were reacted?
A) 2.0 mol
B) 6.0 mol
C) 9.0 mol
D) 18.0 mol
14) If 22.0 g of CO2 are produced, how many grams of H2O are produced?
A) 5.50 g
B) 9.00 g
C) 18.0 g
D) 22.2 g
15) What mass of ZnCl2 can be prepared from the reaction of 3.27 grams of zinc with 3.30 grams of HCl?
Zn +2HCl
A) 6.89 g
ZnCl2 + H2
B) 6.82 g
C) 6.46 g
D) 6.17 g
GASES
16) Calculate the new pressure of helium gas in a balloon if the original volume of 2.5 L at 100.0 kPa increases to 18 L.
A) 0.45 kPa
B) 720 kPa
C) 14 kPa
D) 13 kPa
17) Which of the following is not a basic assumption of kinetic theory?
A) Gases are composed of particles.
B) The particles of all move at the same speed
C) The particles of gases are in constant motion.
D) All collisions of the gas particles are perfectly elastic.
18) If the pressure of a sample of gas increases by a factor of 4, what would happen to the temperature?
A) increase by a factor of 2
C) increase by a factor of 4
B) decrease by a factor of 2
D) decrease to ¼ the original temperature
19) A sample of oxygen occupies 47.2 liters under a pressure of 1240 torr at 25oC. What volume would it occupy at 25oC
if the pressure were decreased to 730 torr?
A) 27.8 L
B) 29.3 L
C) 32.3 L
D) 80.2 L
20) A sample of nitrogen occupies 5.50 liters under a pressure of 900 torr at 25oC. At what temperature will it occupy
10.0 liters at the same pressure?
A) 32oC
B) -109oC
C) 154oC
D) 269oC
21) A real gas most closely approaches the behavior of an ideal gas under conditions of:
A) high P and low T
(C) low P and T
B) low P and high T
(D) high P and T
22) If there is 36 g of water vapor present at STP, what volume is present?
A) 45 L
B) 806 L
C) 0.089 L
D) 1.6 L
THERMODYNAMICS
23) Two reagents are mixed in a flask. The bottom of the flask feels cold. This is an example of what kind of reaction?
A) endothermic
C) isothermic
B) exothermic
D) nucleothermic
24) How many kJ of heat is absorbed when 2.0 kg of liquid water is heated from 18oC to 85oC? (SPECIFIC HEAT WATER =
4.18 J/goC)
A) 0.56 kJ
B) –0.56 kJ
C) 560 kJ
D) 280 kJ
25) A mass of 12 g of a substance absorbs 115 J of heat. The initial temperature was 23.5 oC. After absorbing the heat,
the temperature reads 35 oC. What is the specific heat capacity of the substance?
A) 0.16 J/g oC
C) 0.27 J/g oC
B) 0.83 J/g oC
D) 0.38 J/g oC
26) 4Al (s) + 3O2 (g) ¬ 2Al2O3 (s) ∆H = -3351 kJ
is __________, and therefore heat is __________ by the reaction.
A) exothermic, released
C) endothermic, released
B) exothermic, absorbed
D) endothermic, absorbed
27) Which metal requires the most energy to raise 1.00 g of it by 1.00ºC? (Specific heat capacities: Al: 0.900 J/goC, Cu:
0.385 J/goC, Pb: 0.128 J/goC, Ni: 0.440 J/goC)
A) aluminum
B) copper
C) lead
D) nickel
28) What happens to the water in a calorimeter when an exothermic reaction occurs in it?
A) It absorbs heat, and a drop in temperature is observed.
B) It absorbs heat, and a rise in temperature is observed.
C) It releases heat, and a drop in temperature is observed.
D) It releases heat, and a rise in temperature is observed.
SOLUTIONS
29) What is the molarity of a solution prepared by mixing 7.0 moles of NaCl in 585 mL of solution?
A) 0.081 M
C) 4.0 M
B) 81 M
D) 12 M
30) The substance that is dissolved when a solution is prepared is called
A) solvent
B) excess reagent
C) solute
D) reactant
31) What mass (in grams) of sucrose, C12H22O11, is needed to make 500.0 mL of a 0.200 M solution?
A) 68.4 g
B) 34.2 g
C) 100 g
D) 17.1 g
32) If 2.0 mL of 6.0 M HCl is used to make a 500.0-mL solution, what is the concentration of the dilute solution?
A) 0.24 M
B) 0.30 M
C) 0.024 M
D) 0.83 M
33) What is the volume of a solution that has been diluted to .5 M if the original solution was 2M and 500 mL?
(A) 500 mL
(C) 2000 mL
(B) 100 mL
(D) 50 mL
34) You are asked to prepare 500.0 mL of a 2.00 M solution of NaOH. How many grams of sodium hydroxide do you
need:
A) 50.0 g
C) 40.0 g
B) 20.0 g
D) 80.0 g
35) 83.0 g of solid potassium iodide is dissolved in 250 mL of water. What is the molarity of the solution?
A) 0.5 M
C) 2.0 M
B) 1.0 M
D) 4.0 M
36) What is the molarity of a NaOH solution if there is 250 mL and 2.0 grams of NaOH?
A) 0.20 M
C) 0.40 M
B) 0.30 M
D) 0.60 M
EQUILIBRIUM
37) When a reaction is at equilibrium and more reactant is added, which of the following changes is the immediate
result?
A) The reverse reaction rate remains the same.
B) The forward reaction rate increases.
C) The reverse reaction rate decreases.
D) The forward reaction rate remains the same.
Consider the following system at equilibrium…
2SO2 (g) + O2 (g) + heat
2 SO3 (g)
38) Which direction will the reaction shift if the heat is increased?
A) Left
B) Right
C) No change
39) Which direction will the reaction shift if the pressure is decreased?
A) Left
B) Right
C) No change
40) Which direction will the reaction shift if O2 is increased?
A) Left
B) Right
C) No change
41) Which direction will the reaction shift if SO2 is increased?
A) Left
B) Right
C) No change
42) Which direction will the reaction shift if there is an increase in pressure?
A) Left
B) Right
C) No change
ACIDS/BASES
43) Choose the pH of the solution that is most basic.
A) 11
B) 12.7
C) 6.5
D) 4.0
44) Which of the following represents a conjugate acid-base pair?
A) SO32- and SO2
C) H3O+ and H2
B) CO32- and CO2
D) NH4+ and NH3
45) The pH of a solution is 9. What is its H+ concentration?
A) 1.0 x 10-9M
C) 1.0 x 10-5 M
B) 1.0 x 10-7M
D) 9 M
A chemistry student tests the pH of four different solutions. The results are in the table.
Solution
pH
Lemon Juice
2.5
Milk
6.5
Sea Water
8.5
Ammonia
10.5
46) Which solution is weakly acidic?
A) lemon juice
C) seawater
B) milk
D) ammonia
47) What value of pH corresponds to a strongly basic solution?
A)
pH = 11
C)
pH = 4
B)
pH = 0
D)
pH = 14
48) Strong acids _______________
A) Fully dissociate.
C) precipitate in solution
B) Partially dissociate
D) Are insoluble
49) Ethanoic acid is a weak acid. Which one of the following particulate diagrams best represents ethanoic acid in
solution in water?
A)
C)
B)
D)
50) What is the conjugate acid of HSO4-?
A) H2SO4
C) H2O
B) SO42-
D) H3O+