Question

Which reaction does not occur?

2HF(aq) + Cl2(g) → F2(g) + 2HCl(aq)
2Na(s) + ZnF2(aq) + 2NaF(aq) + Zn(s)
O Fe(s) + CuCl2(aq) → FeCl2(aq) + Cu(s)
0 2HCl(aq) + Mg(s) → MgCl2(aq) + H2(g)

Answer 1

The reaction that does not occur is 2Na(s) + ZnF2(aq) + 2NaF(aq) + Zn(s).

Step-by-step explanation:

The reaction that does not occur is 2Na(s) + ZnF2(aq) + 2NaF(aq) + Zn(s). The reason is that both Na and Zn are more reactive than Hydrogen, so they will replace Hydrogen from compounds and form their respective compounds. So, Na will replace hydrogen from NaF and form Na(s) and HF(aq), and Zn will replace hydrogen from ZnF2 and form Zn(s) and HF(aq). Thus, no net reaction will occur.

Answer 2

Answer:
`2HF(aq)+Cl_2(g)\rightarrow F_2(g)+2HCl(aq)` will not occur.

Step-by-step explanation:

A single replacement reaction is one in which a more reactive element displaces a less reactive element from its salt solution. Thus one element should be different from another element.

A general single displacement reaction can be represented as :

`X+YZ\rightarrow XZ+Y`

a)
`2HF(aq)+Cl_2(g)\rightarrow F_2(g)+2HCl(aq)`

Flourine is more reactive than chlorine and hence this reaction cannot occur.

b)
`2Na(s)+ZnF_2(aq)\rightarrow 2NaF(aq)+Zn(s)`

Sodium is more reactive than zinc and hence the reaction will occur.

c)
`Fe(s)+CuCl_2(aq)\rightarrow FeCl_2(aq)+Cu(s)`

Iron is more reactive than copper and hence the reaction will occur.

d)
`2HCl(aq)+Mg(s)\rightarrow MgCl_2(aq)+H_2(g)`

Magnesium is more reactive than hydrogen and hence the reaction will occur.