7) Mg(s) + 2 HCl(aq) + MgCl2(aq) + H2(g)
What type of reaction is shown above?
A)
decomposition
B)
double replacement
C)
synthesis
D)
single replacement

D)  single replacement

Explanation:

Given reaction:

         Mg       +           2HCl      →      MgCl₂        +        H₂

The reaction shown above is a single displacement reaction.

In a single displacement reaction, a more reactive atom displaces another from a given compound.

The comparison here is between Mg and H.

On the activity series, Mg is higher and more reactive, it will displace H from the solution of HCl. This

This reaction type is called a single replacement reaction.