With reference to fly ash produced by the power plants using the coal as fuel, which of the following statements is/are correct? 1. Fly ash can be used in the production of bricks for building construction 2. Fly ash can be used as a replacement for some

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Q: 68 (IAS/2015)
With reference to ‘fly ash’ produced by the power plants using the coal as fuel, which of the following statements is/are correct?
1. Fly ash can be used in the production of bricks for building construction
2. Fly ash can be used as a replacement for some of the Portland cement contents of concrete
3. Fly ash is made up of silicon dioxide and calcium oxide only, and does not contain any toxic elements.
Select the correct answer using the code given below

question_subject: 

Science

question_exam: 

IAS

stats: 

0,186,18,186,7,9,2

keywords: 

{'fly ash': [0, 0, 0, 1], 'ash': [0, 0, 0, 1], 'coal': [0, 1, 2, 0], 'portland cement contents': [0, 0, 0, 1], 'concrete': [0, 0, 0, 2], 'bricks': [3, 1, 0, 4], 'toxic elements': [0, 0, 0, 1], 'fuel': [1, 0, 5, 14], 'power plants': [0, 0, 0, 7]}

The correct answer is:

1 and 2

Fly ash can be used in the production of bricks for building construction, and it can also be used as a replacement for some of the Portland cement contents of concrete. However, the third statement is incorrect. Fly ash is not made up of silicon dioxide and calcium oxide only; it also contains other elements such as aluminum, iron, and trace amounts of potentially toxic elements.