What gas is liberated when magnesium shavings or chips come in contact with water?

When magnesium shavings or chips come in contact with water, they react to produce magnesium hydroxide and hydrogen gas. The chemical equation for the reaction is: 2 Mg (s) + 2 H2O (l)→2 Mg (OH)2 (aq) + H2 (g). This displacement reaction is characterized by effervescence, a vigorous reaction, and the formation of a white precipitate of magnesium hydroxide.

References:

Reactions of Group 2 Elements with Water - Chemistry LibreTexts1

Magnesium (Mg) and water - Lenntech2