Question

Suppose the combustion of fossil fuels continues to increase until it adds 3.407 × 1013 kilograms of carbon to the atmosphere each year as CO2. Round answers to 1 sig fig.

1. How much CO2 (ℳ = 44.01 g/mol) would be added to the atmosphere?

2. How much glucose (ℳ = 180.15 g/mol) could plants produce via photosynthesis if they took up this entire mass of carbon?

3. How many cubic meters would this mass of glucose occupy? The density of solid glucose is 1.54 g/cm3.

Answer 1

1. mass of CO2 added to the atmosphere = (3.407*10^16/12)*44 = 1.25*10^17 g

in 1 sig fig , answer: 1*10^17 g

2. photosynthesis : 6CO2 + 6H2O ---> C6H12O6 + 6o2

NO of mole of glucose produced = (1.25*10^17/44)*(1/6) = 4.735*10^14 mol

amount of glucose deposited = 4.735*10^14*180.15 = 8.53*10^16 g

answer: 9*10^16 g

3. volume of glucose = m/d = (8.53*10^16/1.54) = 5.54*10^16 cm^3

                        = 5.54*10^16*(10^-2)^3

                        = 5.54*10^10 m^3

answer: 6*10^10 m^3