Question

75% of the first order is completed in 30min calculate the rate constant of the reaction​

Answer 1

$\huge\underline{\underline{\bf \orange{Question-}}}$

75% of the first order is completed in 30min calculate the rate constant of the reaction.

$\huge\underline{\underline{\bf \orange{Solution-}}}$

$\large\underline{\underline{\sf Given:}}$

• a = 100%
• a - x = 100 - 75 ➝ 25%
• time (t) = 30 × 60 ➝ 1800sec

$\large\underline{\underline{\sf To\:Find:}}$

• Rate Constant (K)

$\large{\rm We \:know\:that\:for\:1^{st}\:order\: Reaction- }$

✪$\large{\boxed{\bf \blue{K=\dfrac{2.303}{t}log\dfrac{a}{a-x}} }}$

$\implies{\sf \dfrac{2.303}{1800}×log\dfrac{100}{25}}$

$\implies{\sf \dfrac{2.303}{1800}×log4}$

$\implies{\sf \dfrac{2.303}{1800}×2log2}$

{ log2 = 0.303 }

$\implies{\sf\dfrac{2.303}{1800}×2×0.303 }$

$\implies{\sf \dfrac{1.39}{1800}}$

$\implies{\bf \red{Rate\: Constant (K)=7.7×10^{-4}sec^{-1}} }$

$\huge\underline{\underline{\bf \orange{Answer-}}}$

Rate constant of the reaction is ${\bf \red{7.7×10^{-4}sec^{-1}}}$.