Consider the following statements: 

Statement- I: India despite having uranium deposits, depends on coal for most of its electricity production. 

Statement- II: Uranium, enriched to the extent of at least 60%, is required for the production of electricity. 

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 is the correct explanation for Statement-I 

(b) Both Statement-I and Statement-II are correct and Statement-II is not the correct explanation for Statement-I 

(c) Statement-I is correct but Statement-II is incorrect 

(d) Statement- I is incorrect but Statement- II is correct 

Ans: c

Explanation: 

India’s three-stage nuclear power programme is a long-term plan that involves the use of three different types of reactors to produce energy.

The first stage involves uranium-fueled heavy water reactors (HWRs) that produce plutonium.

The second stage, comprising of Fast Breeder Reactors (FBRs) are fuelled by mixed oxide of Uranium238 and Plutonium239, recovered by reprocessing of the first stage spent fuel

The third and final stage involves using the recovered materials to create 232Th/233U fuel for advanced heavy water reactors (HWRs) 

This programme is necessary because India has abundant thorium reserves but little uranium, and the use of a thorium fuel cycle in the third stage is a key feature of the programme.

Indian Prime Minister  Narendra Modi  in March 2024 witnessed the start of fuel loading at the 500 MWe Prototype Fast Breeder Reactor at Kalpakkam in Tamil Nadu in Fast breeder reactors form the second stage of India’s three-stage nuclear programme.  India is presently in second stage of India’s three-stage nuclear programme

Since thorium is used in the third stage, presently, India depends  substantially on Coal for Power generation 

Hence, statement I is correct.

Uranium is a naturally occurring radioactive element 

There are three natural isotopes of uranium — uranium-234 (U-234), uranium-235 (U-235) and uranium-238 (U-238). U-238 is the most common one, accounting for around 99 per cent of natural uranium found on earth. Most nuclear reactors use fuels containing U-235, however, natural uranium typically contains only 0.72 per cent of U-235 and, most reactors need a higher concentration of this isotope in their fuel. Therefore, the U-235 concentration is being artificially increased through a process called enrichment.  

Uranium enrichment is the process, through which the isotopic proportion of U-235 is increased from 0.72 per cent to up to 94 per cent. 

Uranium is considered low-enriched if its isotopic proportion of U-235 remains below 20 per cent. Most commercial reactors use low-enriched uranium (LEU) below five per cent as fuel, which is also often referred to as “reactor-grade uranium”. LEU does not deteriorate and can be safely stored for many years. 

If uranium is enriched beyond 20 per cent, it is considered highly enriched. Uranium with such high isotopic proportions of U-235 is mostly used in naval propulsion reactors (for example in submarines), nuclear weapons and some research reactors. 

Hence, statement II is incorrect.

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