Problem

Consider the following reactions of three unidentified metals P, Q and R. -

\text{PCl}_2(\text{aq}) + 2\text{Q}(\text{s}) \rightarrow \text{P}(\text{s}) + 2\text{QCl}(\text{aq})

\text{RCl}_2(\text{aq}) + 2\text{Q}(\text{s}) \rightarrow \text{R}(\text{s}) + 2\text{QCl}(\text{aq})

\text{RCl}_2(\text{aq}) + 2\text{P}(\text{s}) \rightarrow \text{no reaction}

Deduce the order of increasing reactivity of the metals. a.

\text{P} < \text{Q} < \text{R}

\text{P} < \text{R} < \text{Q}

\text{R} < \text{P} < \text{Q}

\text{Q} < \text{R} < \text{P}