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CP Chemistry Practice for Final Exam
1. If .50 mole of N2 reacts completely with H2 according to the equation N2 + 3H2  2NH3, the number of
moles of NH3 formed is
a. 1
b. 2
c. 3
d. 0.5
2. How many grams of water, H2O (g), are formed when one mole of butane, C4H10 (g), is burned in
oxygen, O2 (g)?
2 C4H10 (g) + 13 O2 (g)  8 CO2 (g) + 10 H2O (g)
a. 1
b. 5
c. 18
d. 90
3. If 10.0 grams of iron, Fe, and 10.0 grams of sulfur, S, are heated together, how many grams of iron (II)
sulfide, FeS, could be formed?
Fe + S  FeS
a. 10.0
b. 15.7
c. 27.6
d. 88.0
Use the following diagram to answer questions 4-7.
1
2
Temp
3
5
4
heat added
4. The transformation from liquid to gas phase is represented by
a. 1
b. 2
c. 3
d. 4
e. 5
5. The pure gas phase is represented by
a. 1
b. 2
c. 3
d. 4
e. 5
6. Freezing is represented by
a. 1
b. 2
d. 4
e. 5
7.
c. 3
If a substance goes from point 2 to point 5, this would be an ____________ process.
a. Endothermic
b. exothermic
c. both
d. neither
8. Given 1/8 S8 (s) + O2 (g)  SO2 (g) ∆H = -71.0 kcal
SO2 (g) + ½ O2 (g)  SO3 (g) ∆H = -23.5 kcal
What is the heat of reaction, ∆HRXN, for 1/8 S8 (s) + 3/2 O2 (g)  SO3 (g)?
a. -47.5 kcal
b. -94.5 kcal
c. -189 kcal
d. -378 kcal
9. The enthalpy of fusion indicates
a. relative attraction between particles
b. the amount of vapor formed
c. the amount of heat required to melt a solid
d. the bonding angles
10. Which change is represented by the equation below?
H2O (l)  H2O (g)
a. vaporization
b. condensation
c. deposition
d. sublimation
11. How many Joules are needed to raise 50.0 grams of water from 10C to 30C?
a. 4180
b. 10,450
c. 16,720
d. 20,900
12. How many liters of oxygen gas measured at STP will be required to burn 1.00 moles of acetylene gas,
C2H2?
C2H2 + 5/2 O2  2 CO2 + H2O
a. 8.90
b. 56.0
c. 67.2
d. 112
13. When gases are heated, their kinetic energy
a. increases
b. decreases
c. remains the same
d.becomes potential energy
14. What volume is occupied by 1.50 moles oxygen gas at STP?
a. 11.2 L
b. 16.0 L
c. 22.4 L
d. 33.6 L
15. Separate containers of H2 and N2 gas, both containing 1 mole at STP, have
a. different volumes
b. the same molecular weight
c. the same number of molecules
d. equal rates of diffusion
16. What is the molecular geometry, or shape, of a molecule of water
a. linear
b. bent
c. tringonal planar
d. trigonal pyramidal
17. How many grams of calcium carbonate would be needed to produce 44.8 liters of carbon dioxide gas
measured at STP?
CaCO3 + 2 HCl  CaCl2 + H2O + CO2
a. 50
b. 100
c. 111
d. 200
18. A gas has a density of 0.717 g/L at STP. What is the mass in grams of one mole of this gas?
a. 8.00 g
b. 16.1 g
c. 28.1 g
d. 4.00 g
19. At constant temperature, the pressure of a gas increases when the volume
a. increases
b. decreases
c. remains the same
d. can’t be predicted
20. What is the molarity of 100 ml of a solution containing 1.01 grams of potassium nitrate KNO3?
a. 1.00 M
b. 0.00100 M
c. 0.100 M
d. 10.0 M
21. What is the total number of particles formed when (NH4)3PO4 dissolves in water?
a. 1
b. 2
c. 3
d. 4
22. If 6.2 grams of the antifreeze ethylene glycol, C2H6O2, is dissolved in 250 g of water, what will be the
freezing point of the resulting solution?
a. -0.046C
b. -0.74C
c. -7.4C
d. -46C
23. How many grams of sodium sulfate, Na2SO4, are dissolved in 45 mL of a 0.02 M solution?
a. 0.90
b. 6.39
c. .128
d. .00000634
24. Which of the following is not equivalent to the others?
a. 1 cm3 H2O
b. 1 g H2O
c. 1 mL H2O
d. 1 mole H2O
25. Water has a specific heat of 4.184 J/g°C while glass (Pyrex) has a specific heat of 0.780 J/g°C. If 10.0 J
of heat is added to 1.00 g of each of these, which will experience the larger increase of temperature?
a. glass
b. water
c. They both will experience the same change in temperature since only the amount of a substance
relates to the increase in temperature.
26. What is the percent yield of water if 0.90 g of water is obtained when 29.0 g of butane is burned in
excess oxygen? The balanced chemical equation is...
a. 0.02%
b. 2%
c. 10%
d. 36%
27. If 88.0 grams of solid carbon dioxide sublimates, how many liters of CO2 gas will be formed at a
temperature of 300 K and 2.00 atmospheres of pressure? R = 0.08206 (L*atm/mol*K)
a. 98.5 liters
b. 2170 liters
c. 24.6 liters
d. 1080 liters
28. The compound HF would be classified as:
a. Strong acid b. weak acid
c. strong base
d. weak base
29. The salt KF would be considered to be:
a. acidic
b. basic
c. neutral
d. not a salt
30. What is the pH of a .0500 M KOH solution?
a. 1.30
b. 12.7
c. 1.00
d. 13.0
Open Ended Problems
31. If 9.46 g of PF3 are consumed in the following reaction,
2PF3 + XeF4 + 824 kJ 2PF5 + Xe
a. What mass of Xe would be produced?
b. If the reaction has a 95% yield, what is the actual yield of Xe?
c. How much heat is released if the 9.46 g of PF3 is consumed?
32. A balloon contains 50 grams of chlorine gas at STP.
a. calculate initial volume of the gas
b. Compared to the volume above at standard pressure, what would the new volume be if the
pressure was increased to 790 mmHg?
c. Compared to the volume (part a) at STP, what would the new temperature be if the pressure was
decreased to 97 kPa and the volume was increased to 30.0 L?
d. If the volume from part (a) was kept constant, but 12 grams of hydrogen gas were injected into
the balloon, what would the partial pressure of the hydrogen be? What would be the total
pressure inside the balloon?
33. 173 grams of K2SO4 is dissolved into 1.60L of solution. The density of the solution is 1.09 g/mL.
a. what is the Molarity of the solution?
b. what is the molality of the solution?
c. what will the boiling point of this solution be? Kb for water is 0.515 °C/m.
d. what will be the freezing point of this solution be? Kf for water is 1.86 °C/m.
34. Use the thermochemical equations shown below to determine the enthalpy for the final reaction:
2Fe(s) + 3CO2(g)  Fe2O3(s) + 3CO(g)
3FeO(s) + CO2(g)  Fe3O4 + CO(g)
FeO(s) + CO(g)  Fe(s) + CO2(g)
ΔH = 14 kJ
ΔH = 11 kJ
ΔH = 2 kJ
2Fe3O4(s) + CO2(g)  3Fe2O3(s) + CO(g)
ΔH=???
35. What volume of 2.00 M HCl is needed to neutralize 125 ml of 4.00 M KOH?
36. How much heat is needed to convert 10 grams of ice at -25.0 °C, into steam at 175°C?
37. For each of the molecules listed below, draw out the Lewis Structure, then list its molecular geometry
(shape), and indicate if it is polar or nonpolar.
a. H2CO
b. HSiP
38. Balance the following reactions and indicate the type of reaction on the blank to the right.
a. ___ Al(ClO3)3  ____ AlCl3 + ____ O2
_____________________________
b. ____ Mg + ____ SnCl4  ____ Sn + ____ MgCl2 _____________________________
c. ____ C6H14 + ____ O2  ____ CO2 + ____ H2O
_____________________________
39. Refer to the solubility diagram below for the following
questions:
a. How many grams of NH3 Will dissolve in 26g of
water at 10°C?
b. If you have 140 grams of KI in 100 grams of water
at 10°C and you do not see any solute particles, is
this solution saturated, supersaturated, or
unsaturated?
c. If you have 90g of KNO3 at 90°C in 100g of water,
is this solution saturated, supersaturated, or
unsaturated?
d. What is the mass % of a saturated solution of NH4Cl at 70°C?
e. What would the molality be of a saturated solution of KClO3 at 50 °C, if the solute is dissolved in 1.5kg
of water?
40. Given a solution of .000325 M HBr
a. Write out the dissociation equation for the HBr
b. Calculate the:
i. pH = _______________________
ii. pOH = ______________________
iii. [OH-] = _____________________________
iv. [H+] = ______________________________
41. Given a solution of .0875 M Ba(OH)2
a. Write out the dissociation equation for the Ba(OH)2
b. Calculate the:
i. pH = _______________________
ii. pOH = ______________________
iii. [OH-] = _____________________________
iv. [H+] = ______________________________