Ca + 2H2O → Ca(OH)2 + H2 . How many moles of H2O are needed to exactly react with 2.0 moles of Ca?

The number of moles of calcium metal required is 2.0 moles.

Explanation:

We are given:

Moles of water reacted = 4.0 moles

The given chemical reaction follows:

By Stoichiometry of the reaction:

2 moles of water is reacted with 1 mole of calcium metal

So, 4.0 moles of water will react with =  of calcium metal

Hence, the number of moles of calcium metal required is 2.0 moles

Explanation:

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