A first-order reaction has a rate constant of 2.303 × 10^-3 s^-1 . The time required for 40 g of this reactant to reduce to 10 g will be: [Given _10 2 - CHEMISTRY MCQ NEET 2019 2026 | ExamTest.live

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A first-order reaction has a rate constant of 2.303 \times 1 0^{- 3} s^{- 1} . The time required for 40 g of this reactant to reduce to 10 g will be: [Given lo g_{10} 2 = 0.3010]

Solution & Step-by-step Explanation

For a first-order reaction: t = \frac{2.303}{k} lo g \frac{[ A ] _{0}}{[ A ] _{t}} t = \frac{2.303}{2.303 \times 1 0 ^{- 3}} lo g \frac{40}{10} t = 1 0^{3} lo g 4 t = 1000 \times 2 lo g 2 t = 1000 \times 2 \times 0.3010 = 602 s .

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A first-order reaction has a rate constant of 2.303 \times 1 0^{- 3} s^{- 1} . The time required for 40 g of this reactant to reduce to 10 g will be: [Given lo g_{10} 2 = 0.3010]

230.3 s

301 s

2000 s

602 s

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