0.400 mole of sucrose, c12h22o11, contains ________ c atoms.

CHM1010 NAME:__________________

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Exam 2

1. 0.400 mole of sucrose, C12H22O11, contains ________ moles of C. 1pt a) 12

b) 4.80 c) 5.02 × 1022 d) 6.02 × 1023 e) 2.89 × 1024

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2. Which of the following gives the balanced equation for this reaction? K3PO4 + Ca(NO3)2 → Ca3(PO4)2 + KNO3

1 pt

a) 2K3PO4 + Ca(NO3)2 → Ca3(PO4)2 + 6KNO3

b) KPO4 + CaNO3 + KNO3

c) 2K3PO4 + 3Ca(NO3)2 → Ca3(PO4)2 + 6KNO3

d) K3PO4 + Ca(NO3)2 → Ca3(PO4)2 + KNO3

e) K3PO4 + Ca(NO3)2 → Ca3(PO4)2 + 3KNO3

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3. Calculate the molar mass of magnesium chloride, MgCl2 1 pt

a) 59.76 g/mole b) 70.90 g/mole c) 95.21 g/mole d) 125.9 g/mole e) 24.31 g/mole

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4. In the kinetic molecular theory of gas behavior, the assumption is made that gas molecules ________.

1 pt

a) move with a kinetic energy equal to their centigrade temperature b) move rapidly in random directions c) are attracted to each other by strong forces d) are close together in their container e) occasionally come to rest

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5. Allyl sulfide C6H10S, is the substance that gives garlic, onions, and leeks their characteristic odor. Some studies indicate that garlic may be beneficial for the heart and in lowering cholesterol. How many grams of C are in 25.8 g of C6H10S?

3 pt

CHM1010 NAME:__________________

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6. According to Boyle's Law, it has been observed that as the pressure of a gas increases, the volume of the gas decreases. The Kinetic Theory of gases explains this observation with which of the following statements:

1 pt

a) The gas particles get bigger. b) The kinetic energy of the gas particles increases. c) The gas particles strike the walls of the container more often. d) The temperature of the gas increases. e) The gas particles strike the walls of the container with more force.

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7. Balance the following reaction Al(s)+H2SO4(aq)⟶Al2(SO4)3(aq)+H2(g)

2 pt

8. A patient received 2.0 g of NaCl in 8 hours . How many milliliters of a 0.40 % (m/v) NaCl (saline) solution were delivered?

3 pt

9. Use the kinetic molecular theory of gases to explain the following: The pressure of a gas increases with increasing temperature.

1 pt

a) At a higher temperature, the number and force of collisions against the walls of the container is greater.

b) At a higher temperature, gas particles have lower kinetic energy. c) As temperature increases, concentration of gas molecules in a

container increases.

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CHM1010 NAME:__________________

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d) The attractive forces between the particles of a gas increase with temperature.

10. When 4 moles of aluminum are allowed to react with an excess of chlorine gas, Cl2, how many moles of aluminum chloride are produced? 2Al + 3Cl2 → 2AlCl3

1 pt

a) 1 mole b) 2 moles c) 3 moles d) 4 moles e) 5 moles

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11. Acetylene gas, C2H2, reacts with oxygen according to the following equation. If 1 mole of acetylene react completely with sufficient oxygen, how many moles of carbon dioxide are produced? C2H2 + O2 → CO2 + H2O

2 pt

12. A solution which has 12 g of solute dissolved in 200.mL of solution has a m/v concentration of ________.

3 pt

13. Which of the following is a neutralization reaction? 1 pt

a) xcH2O(l) + SO3(g) → H2SO4(aq)

b) 2NO2(g) → 2NO(g) + O2(g)

c) HNO3(aq) + KOH(aq) → H2O (l) + KNO3(aq)

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CHM1010 NAME:__________________

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d) KCl (aq) + NaNO3(aq) → KNO3(aq) + NaCl(aq)

e) 4Na(s) + O2(g) → 2Na2O(s)

14. Hyperbaric therapy uses 100% oxygen at pressure to help heal wounds and infections, and to treat carbon monoxide poisoning. A hyperbaric chamber has a volume of 1610 L . How many kilograms of O2 gas are

needed to give an oxygen pressure of 1.62 atm at 23 ∘C?

3 pt

15. Which of the following molecules can form hydrogen bonds? 1 pt

a) NaH

b) CH4

c) NH3

d) HI

e) BH3

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16. According to the Brønsted-Lowry definition, ________. 1 pt

a) a base is a proton acceptor b) an acid is a proton acceptor c) an acid acts as the solvent d) a base produces H+ ions in aqueous solutions e) a base is a proton donor

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17. When MgO is added to water, will the salt be soluble or insoluble?

1 pt

CHM1010 NAME:__________________

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18. When 25.0 g of KClO3 reacts, how many grams of O2 are produced? KClO3 → KCl + O2

3 pt

19. A solution containing 79.8 g of NaNO3 in 75.0 gH2O at 50 ∘C is cooled to

20 ∘C. Use the solubility data from the table below.

Solubility (g/100gH2O)

Substance 20∘C 50∘C

KCl 34.0 42.6

NaNO3 88.0 114.0

C12H22O11 (sugar) 203.9 260.4

How many grams of NaNO3 remain in solution at 20 ∘C?

2 pt

How many grams of solid NaNO3 came out of solution after cooling?

2 pt

CHM1010 NAME:__________________

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20. Pentane gas, C5H12, undergoes combustion with oxygen to produce carbon dioxide and water.

. a) Write the balanced chemical equation

1 pt

b) How many grams of C5H12 are needed to produce 85 g of water?

2 pt

a) How many grams of CO2 are produced from 26.1 g of O2?

2 pt

21. What is the molarity of a solution containing 5.0 moles of KCl in 2.0 L of solution?

1 pt

a) 4 M b) 25 M c) 2.5 M d) 5.0 M e) 10. M

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22. What volume of 0.10 M NaOH can be prepared from 250. mL of 0.30 M NaOH?

2 pt

CHM1010 NAME:__________________

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23. Consider a 4% starch solution and a 10% starch solution separated by a semipermeable membrane. Which starch solution will decrease in volume as osmosis occurs?

1 pt

a) 4% b) 10% c) Neither exerts osmotic pressure. d) They exert equal osmotic pressures. e) They exert opposite osmotic pressures.

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24. According to LeChâtelier's principle, predict whether adding H2O causes the system to shift in the direction of reactants, products, or no change. NH4+(aq) + H2O(l) ↔ NH3(aq) + H3O+(aq)

1 pt

a) no change b) products c) reactants

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25. Calculate the [H3O+] of the following aqueous solution with the given [OH−]: milk, 2.1×10−8 M

2 pt

26. Which of the following is a buffer system? 1 pt

a) HCl(aq) and NaOH(aq)

b) H2CO3(aq) and KHCO3(aq)

c) NaCl(aq) and NaOH(aq)

d) H2O(l) and HCl(aq)

e) NaCl(aq) and NaNO3(aq)

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