Match List I with List II : List I (Order of reaction) List II...

The unit of rate constant $k$ for an $n$-th order reaction is given by $(\text{mol}\ \text{L}^{-1})^{1-n}\ \text{s}^{-1}$.

For zero order reaction ($n=0$):
Unit $= (\text{mol}\ \text{L}^{-1})^{1-0}\ \text{s}^{-1} = \text{mol}\ \text{L}^{-1}\ \text{s}^{-1}$ (Matches A with IV)

For first order reaction ($n=1$):
Unit $= (\text{mol}\ \text{L}^{-1})^{1-1}\ \text{s}^{-1} = \text{s}^{-1}$ (Matches B with III)

For second order reaction ($n=2$):
Unit $= (\text{mol}\ \text{L}^{-1})^{1-2}\ \text{s}^{-1} = \text{mol}^{-1}\ \text{L}\ \text{s}^{-1}$ (Matches C with I)

For third order reaction ($n=3$):
Unit $= (\text{mol}\ \text{L}^{-1})^{1-3}\ \text{s}^{-1} = \text{mol}^{-2}\ \text{L}^{2}\ \text{s}^{-1}$ (Matches D with II)

Therefore, the correct matching is A-IV, B-III, C-I, D-II.

Answer: A-IV, B-III, C-I, D-II