What is the mass of calcium that has reacted with water, if this forms a hydroxide weighing 4.44 g?

Chemical reaction formula:
Ca + 2H2O = Ca (OH) 2 + H2.
Find the amount of hydroxide:
4.44 / (40+ (16 + 1) * 2) = 0.06 (mol).
It can be seen from the reaction equation that the amount of hydroxyl formed is equal to the amount of reacted calcium, i.e. 0.06 mol.
Find the mass of calcium:
0.06 * 40 = 2.4 (g.)
Answer: 2.4 grams.

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