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JEE Main levelOne or more correct optionsDifficulty 2 of 3ck088

A reaction has a half-life of $50 min$ for $[A]_{0} = 0.80 mol L^{- 1}$ and $25 min$ for $[A]_{0} = 0.40 mol L^{- 1}$ . Select the correct statement(s).

AThe reaction is zero order.
BThe rate constant is $0.0080 mol L^{- 1} mi n^{- 1}$ .
CFor $[A]_{0} = 0.80 mol L^{- 1}$ , $[A]$ after 60 min is $0.20 mol L^{- 1}$ .
DA $0.80 mol L^{- 1}$ sample is completely consumed in $100 min$ .

Answer: A, B, D

Half-life proportional to

[A]_{0}

identifies zero order, with

k = [A]_{0} / (2 t_{1/2}) = 0.80/100 = 0.0080 mol L^{- 1} mi n^{- 1}

. Complete consumption takes

[A]_{0} / k = 100 min

. At 60 min

[A] = 0.80 - 0.0080 \times 60 = 0.32 mol L^{- 1}

, not 0.20.

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