One of the following is not a characteristic of a good fuel. This is:

The fuel having the lowest calorific value is?

There are four fuels which all contain only carbon and hydrogen. The fuel having highest calorific value will be one which has:

Which of the following is not a fossil fuel?

The calorific values of three fuels A, B and C are 33 KJ/g, 150 KJ/g, respectively. A is solid, B is liquid and C is a gas at room temperature. On combustion, both A and B produces carbon dioxide while C explodes forming steam. B and C leave no residue after combustion while A leaves behind some solid residue. Which one of the three fuels is the most ideal? Give two reasons to support your answer.