Chapter 4

Question 1

One liter of fresh water weighs

Answer 1

1.0 kilogram

Question 2

One liter of air weighs

Answer 2

1.25 grams

Question 3

On liter of salt water weighs

Answer 3

1.025 kilograms

Question 4

Air is composed of

Answer 4

20.9% oxygen and 78% nitrogen

Question 5

What is a special mixture of breathing gas that contains different percentages of oxygen and nitrogen than air

Answer 5

Nitrox

Question 6

Underwater objects appear

Answer 6

1/3 closer and larger

Question 7

What results from excess nitrogen forming bubbles in body tissues and circulatory system on too rapid an ascent?

Answer 7

Decompression sickness

Question 8

The narcotic effect of nitrogen at deeper depths is known as

Answer 8

Rapture of the deep

Question 9

Pure oxygen is what at depths greater than 7.5 meters/25 feet?

Answer 9

Toxic

Question 10

Have you cylinders filled at professional diving facilities to avoid

Answer 10

Carbon monoxide poisoning

Question 11

Scuba cylinders should be kept away from this once filled

Answer 11

Extreme heat