Question

53. A first order reaction has a half life period of
69.3 s. At 0.10 mol L- reactant concentration,
the rate will be -
(1) 104 M s-1
(2) 10-3 M s-1
(3) 10-1 M 1
(4) 6.93 x 10-1 M s-1​

Answer 1

$\huge\underline\green{\sf Answer}$

$\large{\boxed{\sf K = {10}^{-2}}}$

$\huge\underline\green{\sf Solution}$

Formula to find Rate (K) for first order Reaction is :-

★$\large{\boxed{\sf K = {\frac{0.693}{{t}^{1/2}}}}}$

Given :-

K = ?

$\sf{{t}^{1/2}}$ = 69.3 sec

NOW PUT THE VALUE :-

$\large{\sf K = {\frac{0.693}{69.3}}}$

$\large{\sf K = {\frac{693×{10}^{-3}}{693×{10}^{-1}}}}$

$\large{\sf K = {10}^{-3+1}}$

$\large{\boxed{\sf K = {10}^{-2} Ms-1}}$

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