Question

When excess of carbon dioxide is passed through lime water, the milkiness first formed diasappears due to

• 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 1

Answer: (B)

Formation of water soluble calcium bicarbonate

Answer 2

: When excess of carbon dioxide is passed in lime water, calcium carbonate is converted to calcium bicarbonate which is soluble, hence the milkiness due to calcium carbonate disappears.

& Milkiness \\ & \end{aligned}}{CaCO_{3}} \downarrow + H_{2}O$$ $$CaCO_{3} + H_{2}O + CO_{2} \rightarrow Ca\underset{\begin{aligned} & So{lub}le \\ & \end{aligned}}{(HCO_{3})_{2}}$$