Question

what is t (0.5) in terms of t(0.75) for first order reaction

Answer 1

Answer:

the term of firlst reaction is 0.75

Answer 2

Answer:

t(0.75) = 2 × t(0.5)

Explanation:

We have given Rate of first order reaction

$t=\dfrac{2.303}{k}log_{10}\dfrac{a}{a_t}$

Where k is rate constant,

a = initial amount of substance and

$a_t = \text{ final amount of substance.}$

Now,

$t(0.5) =\dfrac{2.303}{k}log_{10}\dfrac{a}{(a-0.5a)} \\\\ t(0.5)= {2.303}\ log_{10}\dfrac2k .....(1)$

Similarly for t(0.75)

$t(0.75) =\dfrac{2.303}{k}log_{10}\dfrac{a}{(a-0.75a)} \\\\ t(0.75)= \dfrac{2.303}{k}\ log_{10}\dfrac a{0.25} = \dfrac{2.303}{k}\ log_{10}4\\\\t(0.75) = 2\times2.303 log\dfrac{2}{k}.....(2)$

from equations (1) and (2),

t(0.75) = 2 × t(0.5)