Which of the following substances increases in mass when heated in air?
- Sodium chloride
- lodine crystals
-
magnesium ribbon
- copper (ll) oxide
The correct answer is: C
Explanation
The mass of magnesium ribbon increases when heated in air because it combines with oxygen to form magnesium oxide, a white powder:
The chemical equation for this reaction is:
2Mg + O2 → 2MgO