When $0.002$ moles of a metal $M$ were reacted with an excess of dilute hydrochloric acid, $48\,\text{cm}^3$ of hydrogen was produced at r.t.p. Which equation is correct for this reaction?
- A$2M + 2H^+ \rightarrow 2M^+ + H_2$
- B$M + H^+ \rightarrow M^+ + H$
- C$M + 2H^+ \rightarrow M^{2+} + H_2$
- D$M + 2H^+ \rightarrow M^{2+} + 2H$