Question

The second half of the gas made by heating limestone in contact with water is primarily composed of:

a) Carbon dioxide
b) Oxygen
c) Hydrogen
d) Methane

Answer 1

The second half of the gas made by heating limestone in contact with water is primarily composed of carbon dioxide (CO₂).

Step-by-step explanation:

The second half of the gas made by heating limestone in contact with water is primarily composed of carbon dioxide (CO₂). When limestone (CaCO₃) is heated, it decomposes into calcium oxide (CaO) and carbon dioxide.

When this carbon dioxide reacts with water, it forms a milky solution due to the formation of calcium carbonate (CaCO₃), which is only slightly soluble in water.