The chemical that reacts with vinegar is sodium bicarbonate.
No rock reacts to vinegar.
vinegar
The vinegar reacts with the eggshell, dissolving the eggshell.
Baking Soda. Baking soda, or it's compound sodium bicarbonate, reacts with the acidic acid in vinegar and is the popular duo of many school science experiments - the "Erupting volcano".
There is no specific name for 'something which reacts with vinegar'. Vinegar is ethanoic acid and reacts with various substance. Some examples are alkalis like sodium hydroxide, metal carbonates and alcohols such as ethanol.
vinegar
Vinegar reacts with metals, that we never see vinegar in metal containers.
Sodium Bicarbonate
Vinegar contains Acetic acid that reacts with the copper in the penny.
Calcite is a mineral. It reacts to hydrochloric acid and it will fizz.
Acid in vinegar reacts with sodium monohydrogencarbonate (baking soda) which is present in mentos.