Fill in the blanks in the following statements:
When carbon dioxide is passed through lime water, it turns milky due to the formation of ______.

Explanation

The milkiness in lime water is due to the formation of calcium carbonate which is in the form of suspended particles. When carbon gas is passed in excess, the milkiness disappears due to the formation of soluble calcium hydrogen carbonate.
`underset(("White ppt."))(CaCO_(3(g)))+CO_(2(g))+H_(2)O_((aq))tounderset("Soluble")(Ca(HCO_(3))_(2(aq)))`