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For a first order reaction, the time required for completion of 90% reaction is ‘x’ times the half life of the reaction. The value of ‘x’ is (Given: In 10 = 2.303 and log 2 = 0.3010)

1. 1.12
2. 2.43
3. 3.32
4. 33.31

Correct answer: 3.32

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