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

B. less of carbon but more of hydrogen

C. equal proportions of carbon and hydrogen

D. less of carbon as well as less of hydrogen

Why do we need alternative sources of energy?

Biogas is considered to be a boon to the farmers. Give reasons.

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.

Calorific value and ignition temperature of fuel X are 75 kJ/g and 200C respectively. These values for fuel Y are 50 kJ/g and 750C respectively. On burning, the fuel Y produces only CO₂ while fuel X produces CO₂ and CO. Which of the two is a better fuel? Give two reasons to support your answer.

Most of the fuels contain carbon as one of the constituents. Name a fuel which has very high calorific value but does not contain carbon.

List two practical uses of bio-gas in rural areas.

Which one of the following is not renewable energy technology?

Which of the following is more environment friendly ?