THE AIR AROUND US

Which of the following explains why air is a mixture?
1. Components of air must be separated by chemical means
2. Percentage of components of air varies(not fixed)
3. When separated,the components of air lose their original property
4. Air is slightly acidic
Which two gases make up more than 95% of air?
1. Oxygen and nitrogen
2. Oxygen and carbon dioxide
3. Nitrogen and carbon dioxide
4. Nitrogen and inert gases
1. Oxygen
2. Carbon dioxide
3. Nitrogen
4. Helium
Which statement about the components of gases in exhaled air is correct?
1. The percentage of gas P increases.
2. The percentage of gas S remains the same
3. The percentage of gas R decreases
4. The percentage of gas Q decreases
Bronchitis, lung cancer and heart disease can be caused by
1. cigarette smoke
2. carbon monoxide
3. acid rain
4. CFC
Excessive chlorofluorocarbon is released into the atmosphere by the use of aerosol sprays and air conditioners. This will cause
1. air pollution
2. natural disaster
3. depletion of the ozone layer
4. greenhouse effect
1. carbon dioxide
2. oxygen
3. nitrogen
4. hydrogen
1. oxygen
2. carbon dioxide
3. nitrogen
4. sulphur dioxide
Which of the following is not an inert gas?
1. Neon
2. Argon
3. Hydrogen
4. Krypton
The following are harmful substances in cigarette smoke except
1. tar
2. carbon monoxide
3. oxygen
4. nicotine