The rate constant for a first order reaction is 4.606 × 10^-3 s^-1 . The time required to reduce 2.0 g of the reactant to 0.2 g is: - Chemistry MCQ NEET 2020 E1 2026 | ExamTest.live

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The rate constant for a first order reaction is 4.606 \times 1 0^{- 3} s^{- 1} . The time required to reduce 2.0 g of the reactant to 0.2 g is:

Solution & Step-by-step Explanation

For a first-order reaction: t = \frac{2.303}{k} lo g \frac{[ A ] _{0}}{[ A ]} t = \frac{2.303}{4.606 \times 1 0 ^{- 3}} lo g \frac{2.0}{0.2} t = \frac{1}{2 \times 1 0 ^{- 3}} lo g 10 = \frac{1 0 ^{3}}{2} \times 1 = 500 s

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The rate constant for a first order reaction is 4.606 \times 1 0^{- 3} s^{- 1} . The time required to reduce 2.0 g of the reactant to 0.2 g is:

100 s

200 s

500 s

1000 s

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