1)Which one of the following fuels is the most sustainable?
A. biodiesel
B. uranium
C. brown coal
D. natural gas
Solution
2) Decisions about clean energy with reduced carbon dioxide emissions will have an impact on electricity generation
from brown coal. However, there will be a much smaller impact on the use of black coal for electricity generation.
The following table compares the energy and carbon content of three different coal samples.
On the Coal is not a pure substance and the composition of samples will vary even within one mine. From the data in this table, it can be deduced that the complete combustion of 1 tonne of black coal will generate
3.6 × 107 kJ of energy.
a) Calculate the mass, in tonne, of wet brown coal that is required to generate 3.6 × 107 kJ of energy
Solution
b) Calculate the mass, in tonne, of carbon dioxide that is produced from the complete combustion of this mass of wet brown coal.
Solution
c) What are the most likely reasons for the energy content of wet brown coal being so much lower than the energy content of dried brown coal? Justify your answer.
Solution