Answer :

To identify the type of chemical reaction given:
[tex]\[ Ca + H_2SO_4 \longrightarrow CaSO_4 + H_2 \][/tex]

Let's analyze the reactants and products step-by-step:

1. Reactants:
- Calcium (Ca)
- Sulfuric acid (H_2SO_4)

2. Products:
- Calcium sulfate (CaSO_4)
- Hydrogen gas (H_2)

Next, observe what happens in this reaction:
- Calcium (Ca) reacts with sulfuric acid (H_2SO_4).
- As a result of this reaction, calcium sulfate (CaSO_4) and hydrogen gas (H_2) are formed.

In this reaction, the calcium (Ca) displaces the hydrogen (H) from sulfuric acid (H_2SO_4) to form a new compound, calcium sulfate (CaSO_4), and releases hydrogen gas (H_2).

This type of reaction, where one element (calcium) displaces another element (hydrogen) in a compound (sulfuric acid), is known as a single displacement reaction.

Therefore, the type of chemical reaction given is:
[tex]\[ \boxed{\text{Single Displacement Reaction}} \][/tex]