11

What is hydrogen (H2)?What is hydrogen (H2)?

a. It is a colorless, explosive gas a. It is a colorless, explosive gas with a foul odor.with a foul odor.

b. It is a colorless, odorless and b. It is a colorless, odorless and tasteless, explosive gas.tasteless, explosive gas.

c. It is a colorless, odorless, c. It is a colorless, odorless, tasteless, non-explosive gas.tasteless, non-explosive gas.

d. It is a colorless, odorless, d. It is a colorless, odorless, tasteless, poisonous gas.tasteless, poisonous gas.

22

How is hydrogen formed in a How is hydrogen formed in a mine?mine?

a. It is formed by decomposing a. It is formed by decomposing sulfur compounds.sulfur compounds.

b. It is formed by electrical arcing.b. It is formed by electrical arcing. c. It is formed by mine fires, c. It is formed by mine fires,

explosions and by charging explosions and by charging batteries.batteries.

d. It is formed by decomposing d. It is formed by decomposing timbers.timbers.

33

Is hydrogen explosive?Is hydrogen explosive?

a. Yes, it is explosive over a small a. Yes, it is explosive over a small range.range.

b. No.b. No. c. Yes, it is explosive, but only at c. Yes, it is explosive, but only at

high temperatures.high temperatures. d. Yes, it is explosive over a wide d. Yes, it is explosive over a wide

range.range.

44

What is the specific gravity of What is the specific gravity of hydrogen? hydrogen?

a. It is the heaviest of all gases. a. It is the heaviest of all gases. Specific gravity one and five hundred Specific gravity one and five hundred twenty-nine thousandths. (1.529).twenty-nine thousandths. (1.529).

b. The specific gravity is five hundred b. The specific gravity is five hundred fifty-five thousandths (0.555).fifty-five thousandths (0.555).

c. It is the lightest of all gases. Specific c. It is the lightest of all gases. Specific gravity seven hundredths (0.07).gravity seven hundredths (0.07).

d. The specific gravity is nine hundred d. The specific gravity is nine hundred sixty-seven thousandths (0967).sixty-seven thousandths (0967).

55

What is the weight of one cubic foot of What is the weight of one cubic foot of hydrogen at 60 degrees hydrogen at 60 degrees

Fahrenheit and 30.00 inches of Fahrenheit and 30.00 inches of mercury pressure?mercury pressure?

a. Five hundred fifty-five ten a. Five hundred fifty-five ten thousandths (0.0555) of one pound.thousandths (0.0555) of one pound.

b. Fifty-three ten thousandths b. Fifty-three ten thousandths (0.0053) of one pound.(0.0053) of one pound.

c. Seventy-six thousandths (0.076) c. Seventy-six thousandths (0.076) of one pound.of one pound.

d. Fifty-five thousandths (0.055) of d. Fifty-five thousandths (0.055) of one pound.one pound.

66

What is the explosive range of What is the explosive range of hydrogen?hydrogen?

a. From four and one tenth percent a. From four and one tenth percent (4.1%) to seven and four tenths (4.1%) to seven and four tenths percent (7.4%).percent (7.4%).

b. From forty-one percent (41% to b. From forty-one percent (41% to seventy-four percent (74%).seventy-four percent (74%).

c. From four and one-tenth percent c. From four and one-tenth percent (4.1%) to seventy-four percent (4.1%) to seventy-four percent (74%).(74%).

d. Seven and four tenths percent d. Seven and four tenths percent (7.4%) to forty-one percent (41%).(7.4%) to forty-one percent (41%).

77

What is the ignition What is the ignition temperature of hydrogen?temperature of hydrogen?

a. Six hundred fifty-five (655) a. Six hundred fifty-five (655) degrees Fahrenheit.degrees Fahrenheit.

b. Twelve hundred (1,200) degrees b. Twelve hundred (1,200) degrees Fahrenheit.935 degrees Fahrenheit.Fahrenheit.935 degrees Fahrenheit.

c. Eleven hundred ninety (1,190) c. Eleven hundred ninety (1,190) degrees Fahrenheit.degrees Fahrenheit.

d. Nine hundred thirty-five (935 d. Nine hundred thirty-five (935 degrees Fahrenheit.degrees Fahrenheit.

88

How is hydrogen detected?How is hydrogen detected?

a. By the use of litmus paper.a. By the use of litmus paper. b. By the Riken gas detector.b. By the Riken gas detector. c. By the Bacharach Electronic c. By the Bacharach Electronic

Canary.Canary. d. By chemical analysis.d. By chemical analysis.