Why do the minerals calcite and dolomite bubble with the mineral or its powder are placed in hydrochloric acid? A) Both minerals are metal hydrides, and when placed in hydrochloric acid they give off hydrogen gas. B) Both minerals are sulfides, and the acid reacts to release sulfur dioxide gas. C) The acid reacts with the mineral to release CO₂gas that is bound into the crystal as carbonate ion. D) The acid and the mineral together react with oxygen in the air, releasing CO₂gas.

Question

Quizplus · Accepted Answer

Calcite and dolomite are both carbonate minerals, meaning they contain the carbonate ion (CO₃²⁻). When placed in hydrochloric acid (HCl), the acid reacts with the carbonate ion to release carbon dioxide gas (CO₂), which causes the bubbling. This reaction can be represented by the following equation:
CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O
or
MgCO₃ + 2HCl → MgCl₂ + CO₂ + H₂O

Why Do the Minerals Calcite and Dolomite Bubble with the Mineral