When air is blown from mouth into a test-tube containing lime water, the lime water turned milky due to the presence of
(A) oxygen
(B) carbon dioxide
(C) nitrogen
(D) water vapour
Answer
- Lime water [Ca(OH) 2 ] is a test for Carbon Dioxide [CO 2 ]. CO 2 turns lime water milky.
- When we exhale, carbon dioxide gas is expelled.
- Upon reacting with lime water, calcium carbonate is formed.
- Calcium carbonate is insoluble in water and turns it milky .
So, the correct answer is (b)