Steam changes the colour of anhydrous cobalt(II) chloride from

Correct answer: Blue to pink

Explanation: Anhydrous cobalt(II) chloride, CoCl₂, is blue. In the presence of water (steam), it forms the hydrated salt CoCl₂·6H₂O, which is pink. This colour change is the basis of cobalt chloride paper used as a moisture indicator.

• White to red — Incorrect.
• Blue to white — Incorrect.
• Blue to pink — Correct.
• White to blue — Incorrect.