With reference to green hydrogen, consider the following statements : 1. It can be used directly as a fuel for internal combustion. 2. It can be blended with natural gas and used as fuel for heat or power generation. 3. It can be used in the hydrogen fuel cell to run vehicles. How many of the above statements are correct?
- A.Only one
- B.Only two
- C.All three
- D.None
Correct answer
Explanation
The correct answer is C, All three. Green hydrogen is chemically the same as any hydrogen, so it can be burnt in engines, mixed with natural gas or used in fuel cells.
Green hydrogen is hydrogen made by splitting water through electrolysis, using electricity from renewable sources such as solar and wind, so its production releases almost no carbon dioxide. Grey hydrogen comes from natural gas without capturing the carbon, and blue hydrogen from natural gas with the carbon captured. Hydrogen can be burnt in suitably modified internal combustion engines, and when it burns it gives mainly water vapour. It can be blended in small shares with natural gas in pipelines for heating and power plants. In a fuel cell it combines with oxygen to produce electricity, with water as the only by-product, which is how fuel cell electric vehicles run.
A and B are wrong because all three statements are correct, not just one or two. D is wrong for the same reason.
Exam tip: Green hydrogen = electrolysis with renewable power; grey = natural gas; blue = natural gas + carbon capture.
Practice Questions
View allConsider the following statements :
1. Ballistic missiles are jet-propelled at subsonic speeds throughout their flights, while cruise missiles are rocket-powered only in the initial phase of flight.
2. Agni-V is a medium-range supersonic cruise missile, while BrahMos is a solid-fuelled intercontinental ballistic missile.
Which of the statements given above is/are correct?
- A.1 only
- B.2 only
- C.Both 1 and 2
- D.Neither 1 nor 2
Show answer
Both statements swap the features of ballistic and cruise missiles. A ballistic missile is rocket-powered only in the first, boost phase; after that it follows a high, curved, mostly unpowered path, re-entering the atmosphere at very high speed.
Read the full explanation →Which one of the following countries has its own Satellite Navigation System?
- A.Australia
- B.Canada
- C.Israel
- D.Japan
Show answer
Japan runs its own regional satellite navigation system, the Quasi-Zenith Satellite System (QZSS), also called Michibiki.
Read the full explanation →With reference to agriculture in India, how can the technique of 'genome sequencing', often seen in the news, be used in the immediate future ?
1. Genome sequencing can be used to identify genetic markers for disease resistance and drought tolerance in various crop plants.
2. This technique helps in reducing the time required to develop new varieties of crop plants.
3. It can be used to decipher the host-pathogen relationships in crops.
Select the correct answer using the code given below :
- A.1 only
- B.2 and 3 only
- C.1 and 3 only
- D.1, 2 and 3
Show answer
Genome sequencing helps find useful genes, speeds up breeding and shows how pathogens attack crops. Genome sequencing reads the complete order of bases in an organism's DNA.
Read the full explanation →In the context of proposals to the use of hydrogen-enriched CNG (H-CNG) as fuel for buses in public transport, consider the following statements :
1. The main advantage of the use of H-CNG is the elimination of carbon monoxide emissions.
2. H-CNG as fuel reduces carbon dioxide and hydrocarbon emissions.
3. Hydrogen up to one-fifth by volume can be blended with CNG as fuel for buses.
4. H-CNG makes the fuel less expensive than CNG.
Which of the statements given above is/are correct?
- A.1 only
- B.2 and 3 only
- C.4 only
- D.1, 2, 3 and 4
Show answer
H-CNG lowers carbon dioxide and hydrocarbon emissions, and hydrogen up to about a fifth by volume can be mixed into CNG for buses.
Read the full explanation →Consider the following statements :
Statement I : Of the two major ethanol producers in the world, i.e., Brazil and the United States of America, the former produces more ethanol than the latter.
Statement II : Unlike in the United States of America where corn is the principal feedstock for ethanol production, sugarcane is the principal feedstock for ethanol production in Brazil.
Which one of the following is correct in respect of the above statements?
- A.Both Statement I and Statement II are correct and Statement II explains Statement I
- B.Both Statement I and Statement II are correct but Statement II does not explain Statement I
- C.Statement I is correct but Statement II is not correct
- D.Statement I is not correct but Statement II is correct
Show answer
The United States, not Brazil, is the world's largest ethanol producer, while the feedstocks named in Statement II are right.
Read the full explanation →