The bromination of acetone that occurs in acid solution is represented by this equation $\mathrm{CH}_3…

The bromination of acetone that occurs in acid solution is represented by this equation $\mathrm{CH}_3 \mathrm{COCH}_3(\mathrm{aq})+\mathrm{Br}_2(\mathrm{aq}) \rightarrow \mathrm{CH}_3 \mathrm{COCH}_2 \mathrm{Br}(\mathrm{aq})+\mathrm{H}^{+}(\mathrm{aq})+\mathrm{Br}^{-}(\mathrm{aq})$ These kinetic data were obtained for given reaction concentrations Initial concentrations, M Based on these data, the rate equation is
  1. $\mathrm{Rate}=\mathrm{k}\left[\mathrm{CH}_3 \mathrm{COCH}_3\right]\left[\mathrm{Br}_2\right]\left[\mathrm{H}^{+}\right]$
  2. $\mathrm{Rate}=\mathrm{k}\left[\mathrm{CH}_3 \mathrm{COCH}_3\right]\left[\mathrm{H}^{+}\right]$
  3. $\mathrm{Rate}=\mathrm{k}\left[\mathrm{CH}=\mathrm{COCH}_3\right]\left[\mathrm{Br}_2\right]$
  4. Rate $=\mathrm{k}\left[\mathrm{CH}_3 \mathrm{COCH}_3\right]\left[\mathrm{Br}_2\right]\left[\mathrm{H}^{+}\right]^2$

Solution

In experiment (1) and (2), rate doesn't depend on the concentration of $\mathrm{Br}_2$. So, rate expression will not include $\left[\mathrm{Br}_2\right]$.

Asked in: NEET 2008 (Mains)

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