2 nd semester final exam practice test 2014 38 questions 30 minutes
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2nd Semester Final Exam Practice Test
2014
38 Questions
30 minutes
1. Which does NOT indicate a phase change?
A. A piece of aluminum is heated to it melting point.
B. A liquid is cooled slowly until it turns into a solid.
C. A rock is crushed into a fine sand
D. Water is left in a cup and slowly dissappears.
25 Seconds
2. What affects the speed of a chemical reaction by decreasing the activation
energy of the reaction?
A. Temperature
B. Catalyst
C. Grinding
D. Stirring
20 Seconds
3. What phase(s) of matter is present at .9 atm & 50⁰C?
A. Solid B. Liquid
C. Gas
25 Seconds
4. What is the relationship between Avogadro’s number and H2O?
A. 18.0 g of H2O
B. 22.4 L of H2O
C. 6.02 X 1023 particles of H2O
15 Seconds
5. How much heat is lost to change 12.5 g of H2O (4.184 J/g(°C)) from 80.0°C to
50.0°C?
A. -2620J
B. 2620 J
C. -1570 J
D. 1570 J
1 minute; 15 seconds
6. What is the change in temperature if 95.3 g sample of water gains 1250 J of
energy? Remember the specific heat of water is 4.184 J/g(°C)
A. -95.3 °C
B. 28,471.6 °C
C. 3.13 °C
D. 54.9 °C
1 minute; 15 seconds
7. What is the pressure at the normal melting and boiling point of water?
A. 0 atm C. 0.006 atm
B. 1 atm D. 225 atm
20 Seconds
8. Is the process when a gas changes into a liquid endothermic or exothermic?
H2O(g) H2O(l)
A. Endothermic
B. Exothermic15 Seconds
9. What change takes place when gas at .8atm & 100⁰ C is cooled to 50⁰C?
A. Freezes C. Sublimes
B. Condenses D. Vaporizes
25 Seconds
10. What is the molar volume of a gas?
A. 18.0 g
B. 22.4 L
C. 6.02 X 1023 particles
15 Seconds
11. How many grams are in 2.5 moles of BrO2?
A. 0.022 grams
B. 280 grams
C. 0.034 grams
D. 240 grams
1 minute
12. What is the molar mass of H2SO4?
A. 98.1 grams
B. 145.2 grams
C. 194.4 grams
D. 259.8 grams
45 seconds
13. Reduction is the process by which a substance _____________.
A. Loses one or more electrons
B. Gains one or more electrons
C. Gains one electron
D. Loses one electron
20 seconds
14. Calculate the molarity of a 50.0 g sample of NaCl that is mixed in 150mL of
water.
A. 0.057 M
B. .13 M
C. .13 m
D. 5.7 M
1 minutes 15 seconds
15. Using the equation below, how many grams of NaOH are needed to produce
30.8 L of Na2SO4?
H2SO4 + 2NaOH 2H2O + Na2SO4
A. 110. g
B. 55.0 g
C. 27.5 g
D. .0172 g
1 minute and 30 seconds
16. Using the equation below, how many grams of H2SO4 will you get if you have
58.5 g of NaOH?
H2SO4 + 2NaOH 2H2O + Na2SO4
A. 71.7 g
B. 143 g
C. 287 g
D. 23.9 g
1 minute 30 seconds
17. Base off of Charles’ Law, what happens to a balloon when the
temperature is decreased?
A. The balloon popped
B. The balloon got bigger (increase volume)
C. The balloon got smaller (decrease volume)
D. The balloon volume didn’t change.
25 seconds
18. How much heat will be released if 9.0 g of Na reacts with excess O2?
2Na + O2 Na2O H = -60 kJ
A. 23 kJ
B. -23 kJ
C. 12 kJ
D. -12 kJ
1 minute 15 seconds
19. A gas mixture contains the following gases with the mole fractions indicated: CH4
(0.380), C2H6 (0.325), C3H8 (0.009), and C4H10 (0.057). The mixture also contains C2H2. What is the mole fraction of C2H2?
A. 6.34 X 10-5
B. 0.522
C. 0.571
D. 0.229
40 seconds
20. A sealed plastic bottle has a volume of 2 L at a temperature of 35°C, what is
the temperature if the volume decreases to 1.5 L?
A. -42°C
B. 17°C
C. 231°C
D. .09°C
1 minute
21. A 20. L balloon at standard atmospheric pressure is squeezed and causes a new pressure of 900. mmHg.
What is the new volume of the balloon?
A. 17 L
B. .020 L
C. 24 L
D. .87 L
1 minute
22. 1.5 moles of a gas at 2.3 atm is in a 4.5 L container. What is the
temperature of the gas?
A. 84 ⁰ CB. 84 K
C. 16 ⁰ CD. 16 K
1 minute 15 seconds
23. What is the % by mass of Mn in MnO4?
A. 76.3%
B. 76.4%
C. 46.2%
D. 49.1%1 minute 15 seconds
24. According to Le Chatelier’s principle, a decrease in the concentration of a
product will cause a reaction to:
A. shift to the left
B. shift to produce more of the reactants
C. consume what is left of the products
D. shift to produce more of the products
30 seconds
25. What is the pH of 0.300 M Sr(OH)2
A. 13.8
B. .222
C. .523
D. 13.560 Seconds
26. Systems in nature tend to undergo changes toward
A. higher entropy and higher energy
B. lower entropy and lower energy
C. higher entropy and lower energy
D. lower entropy and higher energy
20 Seconds
27. Fe + 3Cl2 2FeCl3Which way does the reaction shift when you take away some FeCl3
A. Left
B. Right
C. No Shift
20 seconds
28. Fe + 3Cl2 2FeCl3Which will result in an increase in
concentration of FeCl3?
A. Decrease Fe
B. Decrease the pressure
C. Increase Cl2
D. Change the temperature
20 seconds
29. In a direct combination reaction,
A. an element is reduced and the other one
is oxidized
B. all elements are oxidized
C. all elements are reduced
D. it has nothing to do with a redox reaction
20 seconds
30. Which of the following is a property of an acid?
A. Bitter taste
B. Slippery
C. Good conductor of electricity
D. Soothes sunburns
15 seconds
31. The kinetic molecular theory assumes that the particles of an ideal
gas
A. Exert no force on one another
B. Have a volume close to 1
C. Exert great forces on each other during
collisions
A. Move in specific patterns
25 seconds
32. A weak acid . . .
A. totally dissociates in water
B. doesn’t conduct electricity
C. produces H+ ions that form H3O+ ions
D. makes the water basic
15 seconds
33. The end point and equivalence point in an acid base reaction should be
A. at the same point
B. at a difference of 1
C. have pH’s of 6 and 8
D. a point with a concentration of 1.0 M
15 seconds
34. Which is a neutralization reaction?
A. when a carbon compound burns in O2
B. when a molecule splits into its parts
C. when a single replacement reaction takes
place.
D.when H+ ions react with OH- ions
20 seconds
35. In the following reaction, label the oxidation state (number) of
each element before and after the reaction:
2 C2H2 + 5 O2 4 CO2 + 2 H2O
H = H =
O = O =
C = C =
1 ½ minutes
36. Based off of your answers to the previous question, what element(s) are being reduced when the product
is produced? Oxidized?
2 C2H2 + 5 O2 4 CO2 + 2 H2O
A. reduced = C, oxidized = OB. reduced = O, oxidized = CC. reduced = H, oxidized = OD. reduced = O, oxidized = H
30 sec
37. A sample of HCl is considered to be an Arrhenius acid because it dissolves in
water to yield
A. OH+ ions as the only positive ions
B. HCl molecules to make it acidic
C. Cl- ions as the only negative ions
D.H+ ions as the only positive ions
20 seconds
38. What is the hydronium ion concentration when a solution changes
from a pH of 6 to 2?
A. 10,000 times the original content
B. 1,000 times the original content
C. 100 times the original content
D.10 times the original content
45 seconds
Answer Key
1.C 7. B 13. B 19. D25. D
31. A
2. B 8. B 14. D 20. A 26. C 32. C
3. B 9. B 15. A 21. A 27. B 33. A
4. C 10. B 16. A 22. B 28. C 34. D
5. C 11. B 17.C 23. C 29. A
6. C 12. A 18. D 24. D 30. C
Answer Key
38. A
35. H = +1 & +1
O = 0 & -2
C = -1 & +4
36. B
37. D
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