Multiple choice

Why do chalk pieces first float on water, but after sometime sink?

  1. Chalk is white in color.

  2. Chalk is a metal.

  3. Chalk in soluble in water.

  4. Chalk is opaque.

  5. Chalk is porous.

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

Yes, chalk is porous, so it absorbs water; as a result, after some time it becomes heavier and sinks.