Question

Identify the type of reaction in the following examples:
A) $N{a_2}S{O_{4(aq)}} + BaC{l_{2(aq)}} \to BaS{O_{4(s)}} + NaC{l_{(aq)}}$
B) $F{e_{(s)}} + CuS{O_{4(aq)}} \to FeS{O_{4(aq)}} + C{u_{(s)}}$
C) $2{H_{2(g)}} + {O_{2(g)}} \to 2{H_2}{O_{(l)}}$

Answer 1

We know that there are 5 primary types of chemical reactions: combination reaction, displacement reaction, double displacement, decomposition, precipitation reaction. On the left side of the reaction, there are reactants and on the right side, we have a product. Depending on the product formulation we will find out what type of reaction it is.

Complete answer:
To solve this problem first we will discuss various types of reactions.

1. Double displacement reaction- If in a reaction an element gets exchanged between two compounds known as double displacement reaction. These reactions are also known as metathesis reactions.
   $XY + ZA \to XZ + YA$
   Example- $N{a_2}S{O_4} + BaC{l_2} \to BaS{O_4} + 2NaCl$
   Here in this reaction ion exchange takes place. This reaction is an example of double displacement.
2. Displacement reaction- When a more reactive element displaces a less reactive element from its aqueous salt solution known as displacement reaction. Sometimes it’s called a substitution reaction.
   $X + YZ \to XZ + Y$
   Example – $CuS{O_4} + Fe \to FeS{O_4} + Cu$
   Here in this reaction copper is replaced by iron. Because iron is more reactive than copper. This reaction is an example of a displacement reaction.
3. Combination reaction- When two or more reactants react to each other to form a product known as a combination reaction. These reactions are also known as synthesis reactions.
   $A + B \to C$
   For example - $2{H_{2(g)}} + {O_{2(g)}} \to 2{H_2}{O_{(l)}}$
   In this reaction hydrogen molecules combine with oxygen molecules to give water. This reaction is an example of a combination reaction.

Note:
Double displacement reactions usually occur in aqueous solutions in which ions precipitate and ions are exchanged. Double displacement reactions can be further classified as neutralization, precipitation and gas formation reactions. There must also be a double displacement reaction when an insoluble gas is formed. One important thing to remember with a single displacement reaction is that the elements that make up the cations can only move the cations, and the elements that form the anions can only move the anions.