At 345 K, the half life for the decomposition of a sample of a gaseous compound initially at 55.5 kPa was 340 s. When the pressure was 27.8 kPa, the half life was found to be 170 s. The order of the reaction is ____________. [integer answer]
Answer (integer)
0
Solution
$t_{1 / 2} \propto \frac{1}{\left[P_{0}\right]^{n-1}}$
<br/><br/>
$$
\begin{aligned}
&\frac{\left(\mathrm{t}_{1 / 2}\right)_{1}}{\left(\mathrm{t}_{1 / 2}\right)_{2}}=\frac{\left[\mathrm{P}_{0}\right]_{2}^{\mathrm{n}-1}}{\left[\mathrm{P}_{0}\right]_{1}^{\mathrm{n}-1}} \\\\
&\frac{340}{170}=\left(\frac{27.8}{55.5}\right)^{\mathrm{n}-1} \\\\
&2=\left(\frac{1}{2}\right)^{\mathrm{n}-1} \\\\
&2=(2)^{1-n} \\\\
&1-\mathrm{n}=1 \\\\
&\mathrm{n}=0
\end{aligned}
$$
About this question
Subject: Chemistry · Chapter: Chemical Kinetics · Topic: Rate of Reaction
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