EVERYDAY SCIENCE

Detailed explanation-1: -This carbon dioxide is present in the air that we exhale. When we blow into a test tube containing limewater (calcium hydroxide), the carbon dioxide reacts with it and turns it milky. This milky appearance is due to the formation of calcium carbonate.

Detailed explanation-2: -Limewater is a solution of calcium hydroxide. If carbon dioxide is bubbled through limewater, the limewater turns milky or cloudy white.

Detailed explanation-3: -Lime Water is also known as calcium hydroxide. When exhaled air is blown through lime Water, it turns milky. The carbon dioxide present in the exhaled air reacts with the lime water and turns it into a milky solution.

Detailed explanation-4: -Reaction with limewater Carbon dioxide reacts with limewater (a solution of calcium hydroxide, Ca(OH) 2), to form a white precipitate (appears milky) of calcium carbonate, CaCO 3.

Detailed explanation-5: -Procedure: Add limewater into the glass and cover it with a lid. Put a straw into the lid’s hole. Observation: The limewater in the glass turns milky. Conclusion: The exhaled air being blown into the lime water contains carbon dioxide. As a result, carbon dioxide is present in exhaled air.