Question
Which of the following metals does not liberate hydrogen
gas when reacted with cold water but does so with steam?Solution
Magnesium reacts very slowly with cold water, and the reaction may not be observable at room temperature. However, when heated with steam, magnesium reacts more vigorously, forming magnesium oxide (MgO) and hydrogen gas (H ₂ ). Reaction with steam: Mg (s) + H ₂ O (g) → MgO (s) + H ₂  (g)
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