Definitions

Question 1

Define gas

Answer 1

A gas is a substance that has no well-defined boundaries but diffuses rapidly to fill any container in which it is placed

Question 2

How is temperature converted from the Celsius scale to the kelvin scale?

Answer 2

Temperature can be converted from the Celsius scale to the kelvin scale by adding 273.

Question 3

What is the normal atmospheric pressure in pascals and kilopascals?

Answer 3

Normal atmospheric pressure = 1 x 10^5Pa = 100 kPa

Question 4

What is the standard pressure in pascals and kilopascals?

Answer 4

1 x 10^5Pa = 100kPa

Question 5

Define Boyle’s law

Answer 5

Boyle’s law states that, at constant temperature, the volume of a fixed mass of gas is inversely proportional to its pressure

Question 6

Define Charles’ law

Answer 6

Charles’ law states that, at constant pressure, the volume of a fixed mass of gas is directly proportional to its temperature measured on the kelvin scale

Question 7

Define Gay-Lussac’s Law of Combining Volumes

Answer 7

Gay-Lussac’s Law of Combining Volumes states that, in a reaction between gases, the volumes of the reacting gases and the volumes of any gaseous products are in the ratio of small whole numbers provided the volumes are measured at the same temperatures and pressure.

Question 8

Define Avogadro’s Law

Answer 8

The law states that equal volumes of gases contain equal numbers of molecules under the same conditions of temperature and pressure

Question 9

At s.t.p. one mole of any gas occupies a volume of what?

Answer 9

At s.t.p. one mole of any gas occupies a volume of 22.4 litres

Question 10

Define an ideal gas

Answer 10

An ideal gas is one that perfectly obeys all the assumptions of the kinetic theory of gases under all conditions of temperature and pressure

Question 11

Define real gases

Answer 11

Real gases differ from ideal gases because (i) forces of attraction and repulsion do exist between the molecules and (ii) the volume of the molecules is not negligible