What may be expected to happen when phosphine gas is mixed with chlorine gas.

${\mathrm{PH}}_3 \mathrm{and} {\mathrm{Cl}}_2$ is formed with warming up

${\mathrm{PCl}}_5\text{ and }\mathrm{HCl}$ are formed and the mixture cools down

The mixture only cools down

${\mathrm{PCl}}_3\text{ and }\mathrm{HCl}$ are formed and the mixture warms up