Properties of Gases (5.1.1)

Question 1

• The molecules of a gas are very far apart, have a high velocity, and fill up the
space in which they are contained.

Answer 1

• The molecules of a gas are very far apart, have a high velocity, and fill up the
space in which they are contained.

Question 2

• Gases are quantified using volume and pressure.

Answer 2

• Gases are quantified using volume and pressure.

Question 3

• Pressure can be measured using a mercury barometer or an open-ended
manometer.

Answer 3

• Pressure can be measured using a mercury barometer or an open-ended
manometer.

Question 4

The molecules of a gas are very far apart. This
makes gases very compressible.
Unlike in solids and liquids, the molecules of a gas
have a high velocity.
The molecules of a gas fill up the space in which
they are contained.
Gases are quantified using volume and pressure.
Volume is measured in units of liters (L).
1 L = 1000 cm3
.
Pressure is force (F) per unit area (A). The force
exerted by the atmosphere at sea level is 14.7
pounds per square inch (psi), or 1 atmosphere
(atm).
Against a perfect vacuum, 1 atm pressure can push
a column of water up 32 feet. A lower pressure
would push the column of water to a lower height. A
denser liquid, such as mercury, has a lower
maximum height.
Atmospheric pressure can be measured using a
mercury barometer. At sea level, the mercury in the
column will be pushed up 760 mm. This allows
pressure to be measured in units of millimeters of
mercury (mmHg), where 760 mmHg = 1 atm.
Another unit of pressure is the torr, where
1 torr = 1 mmHg.
The pressure of a gas sample can be measured
using an open-ended manometer. The difference in
height (in millimeters) between the mercury columns
on the two sides of the manometer shows the
difference in pressure from 760 mmHg (1 atm).

Answer 4

The molecules of a gas are very far apart. This
makes gases very compressible.
Unlike in solids and liquids, the molecules of a gas
have a high velocity.
The molecules of a gas fill up the space in which
they are contained.
Gases are quantified using volume and pressure.
Volume is measured in units of liters (L).
1 L = 1000 cm3
.
Pressure is force (F) per unit area (A). The force
exerted by the atmosphere at sea level is 14.7
pounds per square inch (psi), or 1 atmosphere
(atm).
Against a perfect vacuum, 1 atm pressure can push
a column of water up 32 feet. A lower pressure
would push the column of water to a lower height. A
denser liquid, such as mercury, has a lower
maximum height.
Atmospheric pressure can be measured using a
mercury barometer. At sea level, the mercury in the
column will be pushed up 760 mm. This allows
pressure to be measured in units of millimeters of
mercury (mmHg), where 760 mmHg = 1 atm.
Another unit of pressure is the torr, where
1 torr = 1 mmHg.
The pressure of a gas sample can be measured
using an open-ended manometer. The difference in
height (in millimeters) between the mercury columns
on the two sides of the manometer shows the
difference in pressure from 760 mmHg (1 atm).