Which of the following reactions correctly describes a chemical property of acids?

Acids react with bases (like NaOH) in a neutralization reaction to form a salt and water. The general reaction is:

For example:

Option A states "Acid + NaOH → Normal Salt + CO$_2$". The production of $\text{CO}_2$ is incorrect for a simple acid-base neutralization.

Acids react with metal carbonates ($\text{X}_n\text{CO}_3$) to produce a salt, water, and carbon dioxide gas. The general reaction is:

For example:

This reaction correctly describes a chemical property of acids.

Option C states "Acid + XCO$_3$ → Salt + H$_2$O + NH$_3$". While acids react with carbonates to produce salt, water, and carbon dioxide, they do not produce ammonia ($\text{NH}_3$) in this reaction. Ammonia is typically produced from reactions involving ammonium compounds or nitrogen-containing bases.

Option B accurately describes a chemical property of acids.

The final answer is $\boxed{\text{B}}$