Solutions Quiz 1

1. A water solution of sodium chloride is a good conductor of electricity. Because of this property, table salt is classified as a:

Semi-electrolye

Weak electrolyte

Strong electrolyte

Nonelectrolyte

2. An unknown substance dissolves readily in water but not in benzene (a nonpolar solvent). Molecules of what type are present in the substance?

Neither polar nor nonpolar

Polar

Either polar or nonpolar

Nonpolar

3. An event requires 8.4 milliseconds. This is the same interval of time as:

840000 nanoseconds

0.0084 seconds

0.0000084 seconds

0.0084 microseconds

All of these measure the same interval

4. How many grams of NaCl are contained in 350. mL of a 0.250 M solution of sodium chloride?

41.7 g

5.11 g

14.6 g

87.6 g

None of these

5. A 20.0 g sample HF is dissolved in water to give 200. mL of solution. The concentration of the solution is:

1.0 M

3.0 M

0.10 M

5.0 M

10.0 M

6. Which of the these samples has the smallest mass?

160 ug

0.016 g

0.00016 mg

0.00000016 kg

0.0016mg

7. In 1928, 1.0 g of a new element was isolated from 660 kg of the ore molybdenite. The percent by mass of this element in the ore was:

1.5%

6.6%

1.0%

0.00015%

0035%

8. Which of the following is the smallest mass?

0.001219 g

0.0165 mg

923.1 ug

0.0000023440 kg

39000 cg

9. It is estimated that uranium is relatively common in the earth's crust, occurring in amounts of 4 g/metric ton. A metric ton is 1000 kg. At this concentration, what mass of uranium is present in 1.0 mg of the earth's crust?

4 nanograms

4 micrograms

4 milligrams

0.00004 g

4 centigrams

10. 1.00 mL of a 0.00035 M solution of oleic acid is diluted with 9.00 mL of petroleum ether, forming solution A. 2.00 mL of solution A is diluted with 8.00 mL of petroleum ether, forming solution B. How many grams of oleic acid are in 5.00 mL of solution B? (molar mass for oleic acid = 282 g)

0.000494 g

0.0000007 g

0.0000494 g

0.00000197 g

0.00000987 g