passwella.
Menu

JAMB Chemistry 1990 Question 1

Question 1

Separation of Mixtures

Which of the following is a physical change?

  1. A.The bubbling of chlorine into water.
  2. B.The bubbling of chlorine into a jar containing hydrogen
  3. C.The dissolution of sodium chloride in water.
  4. D.The passing of steam over heated iron
Show the answer and explanation

Answer: C (The dissolution of sodium chloride in water.)

Explanation

Dissolving salt in water makes no new substance; evaporating the water gives the salt back. Chlorine reacts with water and with hydrogen, and steam reacts with hot iron, so those are chemical changes.