Chemistry

Problem

For the elementary gas-phase reaction

2\,\mathrm{X}(g)+\mathrm{Y}(g)\rightarrow\mathrm{Z}(g)

, concentrations are measured in

\text{mol L}^{-1}

and time in

\text{s}

. Which combination of rate law and corresponding units for

k

is correct? a) rate

=k[\mathrm{X}]^{2}[\mathrm{Y}]^{2}

;

k

\text{L}^{3}\,\text{mol}^{-3}\,\text{s}^{-1}

b) rate

=k[\mathrm{X}]^{2}[\mathrm{Y}]

;

k

\text{L\;mol}^{-1}\,\text{s}^{-1}

c) rate

=k[\mathrm{X}]^{2}[\mathrm{Y}]

;

k

\text{L}^{2}\,\text{mol}^{-2}\,\text{s}^{-1}

d) rate

=k[\mathrm{X}][\mathrm{Y}]

;

k

\text{L\;mol}^{-1}\,\text{s}^{-1}