Respuesta :

Answer:

It will take 188.06 hours for the concentration of A to decrease 10.0% of its original concentration.

Explanation:

A → B

Initial concentration of the reactant = x

Final concentration of reactant = 10% of x = 0.1 x

Time taken by the sample, t = ?

Formula used :

[tex]A=A_o\times e^{-\lambda t}\\\\\lambda =\frac{0.693}{t_{\frac{1}{2}}}[/tex]

where,

[tex]A_o[/tex] = initial concentration of reactant

A = concentration of reactant left after the time, (t)

[tex]t_{\frac{1}{2}}[/tex] = half life of the first order conversion  = 56.6 hour

[tex]\lambda[/tex] = rate constant

[tex]A=A_o\times e^{-(\frac{0.693}{t_{1/2}})\times t}[/tex]

Now put all the given values in this formula, we get

[tex]0.1x=x\times e^{-(\frac{0.693}{56.6 hour})\times t}[/tex]

t = 188.06 hour

It will take 188.06 hours for the concentration of A to decrease 10.0% of its original concentration.