The decomposition of acetaldehyde is a second order reaction with a rate constant of $4.71 \times 10^{-8} \mathrm{L} \mathrm{mol}^{-1} \mathrm{s}^{-1}$ What is the instantaneous rate of decomposition of acetaldehyde in a solution with a concentration of $5.55 \times 10^{-4}$
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