A. synthesis.
b. decomposition.
c. double replacement.
d. single replacement.
me

Double replacement

Explanation:

The given reaction is double replacement reaction.

CaCO₃ + 2HCl  → CaCl₂ + H₂CO₃

Double replacement:

It is the reaction in which two compound exchange their ions and form new compounds.

AB + CD → AC +BD

while,

Synthesis reaction:

It is the reaction in which two or more simple substance react to give one or more complex product.

Decomposition:

It is the reaction in which one reactant is break down into two or more product.

AB → A + B

Single replacement:

It is the reaction in which one elements replace the other element in compound.

AB + C → AC + B

answer: e.   sour taste

explanation: acids are those substances which dissociates in water to give ions. as they dissociate to give ions, they act as electrolytes and thus are electrically conductive. acids are sour in taste. example: hcl

bases are those substances which dissociates in water to give ions or accepts ions. as they dissociate to give ions, they act as electrolytes and thus are electrically conductive. bases are bitter in taste. bases are slippery in nature.