Tag: substances, objects and energy

Questions Related to substances, objects and energy

Methane gas is an organic fuel obtained from the sources mentioned here. Which of the following is not a correct source?

chemistry occurrence of carbon compounds in nature substances, objects and energy alternative fuels and energy sources alternative sources of energy

  1. Coal gas

  2. Molasses

  3. Natural gas

  4. Sewage

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Correct Option: B
Explanation:

Molasses is a factory waste from sugar industry. It does not contain any traces of methane. So, methane is not obtained from molasses.

Which among the following is considered as the cleanest fuel?

chemistry occurrence of carbon compounds in nature substances, objects and energy alternative fuels and energy sources alternative sources of energy

  1. Cow dung cake

  2. Petrol

  3. Kerosene

  4. Hydrogen gas

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Correct Option: D
Explanation:

Hydrogen gas is considered as the cleanest fuel because when hydrogen burns in air, it produces nothing but water vapour.

How wars and attacks can act as reason for energy crisis?

chemistry occurrence of carbon compounds in nature substances, objects and energy alternative fuels and energy sources alternative sources of energy

  1. Wars between countries can also hamper supply of energy specially if it happens in Middle East countries like Saudi Arabia, Iraq, Iran, Kuwait, UAE or Qatar

  2. It will attract MNCs to invest int those countries

  3. It will cause the death of people

  4. It will decrease the price of fossil fuels

Show answer
Correct Option: A
Explanation:

Wars between countries can also hamper supply of energy specially if it happens in Middle East countries like Saudi Arabia, Iraq, Iran, Kuwait, UAE or Qatar. Thats what happened during 1990 Gulf war when price of oil reached its peak causing global shortages and created major problem for energy consumers.

Which of the following is not true about Biogas? 

chemistry occurrence of carbon compounds in nature substances, objects and energy alternative fuels and energy sources alternative sources of energy

  1. It contains methane

  2. Burns without smoke

  3. Leaves ash behind

  4. Produced by anaerobic decomposition of animal and plant waste

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Correct Option: C
Explanation:

Higher the methane content, higher the calorific value. Pure $CH _4$ has a Gross Calorific Value of 39.8 $MJ/m^3$. the rate of combustion of biogas is quite high as it is produced by anaerobic decomposition of animal and plant waste.
It does not leave any ash behind after burning as cow dung and other organic matter is used in the preparation of biogas.