Question

Balance each of the following redox reactions and classify it as a combination, decomposition, or displacement reaction:

$\left(a\right)Ca\left(s\right)+H_{2}O\left(l\right)\to Ca{\left(OH\right)}_2\left(aq\right)+H_2\left(g\right)$

$\left(b\right)NaN{O}_3\left(s\right)\to NaN{O}_2\left(s\right)+O_2\left(g\right)$

$\left(c\right)C_2{H}_2\left(g\right)+H_2\left(g\right)\to C_2{H}_6\left(g\right)$

Short answer

The classifications of the given reactions are:

(a) Displacement reaction

(b)Decomposition reaction

(c) Combination reaction

Step-by-step solution

Write balanced reaction of equation (a) 

The given reaction is:

$Ca\left(s\right)+H_{2}O\left(l\right)\to Ca{\left(OH\right)}_2\left(aq\right)+H_2\left(g\right)$

The balanced reaction is:

$Ca\left(s\right)+2H_{2}O\left(l\right)\to Ca{\left(OH\right)}_2\left(aq\right)+H_2\left(g\right)$

The given redox reaction is a displacement reaction.

The calcium atom replaces two hydrogen atoms and forms$Ca{\left(OH\right)}_2.$

Write balanced reaction of equation (b) 

The given reaction is:

$NaN{O}_3\left(s\right)\to NaN{O}_2\left(s\right)+O_2\left(g\right)$

The balanced reaction is:

$2NaN{O}_3\left(s\right)\to 2NaN{O}_2\left(s\right)+O_2\left(g\right)$

The given redox reaction is a decomposition reaction.

In this reaction,$NaN{O}_3$ decomposes and forms$NaN{O}_2$ and$O_2.$

Write balanced reaction of equation (c)

The given reaction is:

$C_2{H}_2\left(g\right)+H_2\left(g\right)\to C_2{H}_6\left(g\right)$

The balanced reaction is:

$C_2{H}_2\left(g\right)+2H_2\left(g\right)\to C_2{H}_6\left(g\right)$

The given redox reaction is a combination reaction.

In this reaction,$C_2{H}_2$and$H_2$ combines and forms$C_2{H}_6.$