Question 5:  CO2  comprises 0.05 percent (1/20 of 1 %) by weight of the atmosphere (see table 1).  What is the weight of  CO2  in tonnes in the atmosphere?

Answer:

Weight of CO2 = 0.005 tonnes / M2

Explanation:

Weight of the atmosphere = 1kg/cm2

Weight of atmosphere per square meter = 10000cm2 * 1kg

= 10000kg/M2

weight of atmosphere in tonnes = 10000kg/1000kg

= 10 tonnes

of this 0.05% is CO2, therefore,

weight of CO2 = (0.05/100) * 10

= 0.005 tonnes / M2

Question 6:    World CO2  emission from deforestation and burning of fossil fuel exceeds 7.7 billion tonnes per year and is increasing.   What percentage of the total amount of CO2    in the atmosphere (calculated in Question 5) is 7.7 billion (7.7 X 109) tonnes.

Answer: