Q4.87P

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

$(a) C a (s) + H_{2} O (l) \to C a {(O H)}_{2} (a q) + H_{2} (g)$

$(b) N a N O_{3} (s) \to N a N O_{2} (s) + O_{2} (g)$

$(c) C_{2} H_{2} (g) + H_{2} (g) \to C_{2} H_{6} (g)$

Verified

Answer

The classifications of the given reactions are:

(a) Displacement reaction

(b)Decomposition reaction

1Step 1: Write balanced reaction of equation (a)

The given reaction is:

$C a (s) + H_{2} O (l) \to C a {(O H)}_{2} (a q) + H_{2} (g)$

The balanced reaction is:

$C a (s) + 2 H_{2} O (l) \to C a {(O H)}_{2} (a q) + H_{2} (g)$

The given redox reaction is a displacement reaction.

The calcium atom replaces two hydrogen atoms and forms $C a {(O H)}_{2} .$

2Step 2: Write balanced reaction of equation (b)

The given reaction is:

$N a N O_{3} (s) \to N a N O_{2} (s) + O_{2} (g)$

The balanced reaction is:

$2 N a N O_{3} (s) \to 2 N a N O_{2} (s) + O_{2} (g)$

The given redox reaction is a decomposition reaction.

In this reaction, $N a N O_{3}$ decomposes and forms $N a N O_{2}$ and $O_{2} .$

3Step 3: Write balanced reaction of equation (c)

The given reaction is:

$C_{2} H_{2} (g) + H_{2} (g) \to C_{2} H_{6} (g)$

The balanced reaction is:

$C_{2} H_{2} (g) + 2 H_{2} (g) \to C_{2} H_{6} (g)$

The given redox reaction is a combination reaction.

In this reaction, $C_{2} H_{2}$ and $H_{2}$ combines and forms $C_{2} H_{6} .$