A first order reaction has a rate constant 1.15 × 10^{-3} s^{-1}. How long will 5 g of this reactant take to reduce to 3 g?

Given-

Rate constant, k = 1.15 × 10^{-3} s^{-1}

Initial quantity, R_{0} = 5 g

Final quantity, R = 3 g

According to the formula of first order reaction,

t =

t = 443.8 s

t = 4.438 × 10^{2} s

__The time taken for 5g of the reactant to reduce to 3 g is 4.438 × 10 ^{2} s__

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