At 30ºC, the half life for the decomposition of \(AB_2\) is 200 s and is independent of the initial concentration of \(AB_2\). The time required for 80% of the \(AB_2\) to decompose is(Given : \(log\; 2 = 0.30,\; log \;3 = 0.48\))
- 200 s
- 323 s
- 467 s
- 532 s
The Correct Option is C
Solution and Explanation
Since, half life is independent of the initial concentration of \(AB_2\).
Hence, reaction is “First Order”.
\(k =\frac{ 2.303 log\;2}{t_{1/2}}\)
\(\frac{2.303 log\;2}{t_{1/2}} = \frac{2.303}{t} \log\frac{100}{(100−80)}\)
\(\frac{2.303 \times 0.3 }{200} = \frac{2.303 }{ t }\log5\)
\(t = 467 \;s\)
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Concepts Used:
Half-life
The amount of time taken for half of a particular sample to react is known as Half-life.
Half-Life Formula:
We can describe exponential decay by any of the three formulas
