Question

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

NCERT Class X
Science - Exemplar Problems

Chapter_Life Processes

Answer 1

B. Carbon dioxide is the correct answer

Answer 2

When air is blown from mouth into a test- tube containing lime water, the lime water turned milky due to the presence of carbon dioxide.

Option (b)

Explanation:

• When we exhale, carbon dioxide is produced in the process. Lime water is calcium hydroxide. The lime water is turned into milky due to formation of calcium carbonate when the lime water reacts with carbon dioxide.

• The reaction is given below:

$\mathrm{Ca}(\mathrm{OH})_{2}+\mathrm{CO}_{2} \rightarrow \mathrm{CaCO}_{3}+\mathrm{H}_{2} \mathrm{O}$

• The products formed in this reaction is calcium carbonate and water.

Learn more about carbon dioxide

Carbon dioxide which is a gas under normal conditions of temperature and pressure can be liquefied by compressing it to 70 atm at ordinary temperature. What happens when pressure is suddenly released?

https://brainly.in/question/435578

Why carbon dioxide is transported in the dissolve form in our blood as compared to oxygen?

https://brainly.in/question/3135656