Multiple choice

When water is boiled, bubbles can be seen coming up from the bottom of the pan. Which of the following is present in the water?

  1. Live microorganisms

  2. Carbon-dioxide

  3. Dissolved air in water

  4. Atmospheric oxygen entering water

  5. Excess of nitrogen gas in water as in atmosphere

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Yes, when water is boiled, air bubbles can be seen coming up from the bottom of the pan. This simple activity shows that air is present in water.