When `CO_2` is passed through lime water , the milkines first formed is due to the formation of ………………….

Options

A. the reversible reaction taking place
B. formation of water soluble calcium bicarbonate
C. huge amount of heat evolved during the reaction
D. formation of water soluble complex of calcium

Answer

B

Explanation

when excess of carbon dioxide is passed in lime water, calcium carbonate is converted to calcium bicarbonae which is soluble, hence the milkiness due to calcium carbonate disappears.
`Ca(OH)_(2) CO_(2) to underset("Milkness")(CaCO_(3)) dArr + H_(2) O`
`CaCO_(3) + H_(2) O + CO_(2) to Ca underset("Soluble")((HCO_(3))_(2))`