\begin{matrix}[\frac{\mathrm{ln}2}{{t}_{1/2}}]{t}_{90%}=\mathrm{ln}[\frac{100}{10}]=\mathrm{ln}10 \\ {t}_{90%}\times \frac{0.693}{{t}_{1/2}}=2.303 \\ {t}_{90%}=\frac{2.303}{0693}\times {t}_{1/2}=3.32{t}_{1/2}\end{matrix}
Hence, x=3.32
For a first order reaction, the time required for completion of 90 reaction is 'x' times the half life of the reaction. The value of 'x' is
(Given: ln10=2.303 and log2=0.3010)
Held on 24 Jun 2022 · Verified 6 Jul 2026.
1.12
2.43
3.32
33.31
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