Question

The number of moles of oxygen gas needed to react with 4.0 moles of mg is

Answer 1

For four moles of mg we need 2 moles of oxygen to react completely

Answer 2

The number of moles of $O_2$ gas needed to react will be "2.0 moles".

According to the question,

Numbers of Mg,

• 4.0 moles

Now,

→ $4.0 \ moles \ of \ Mg\times \frac{1 \ mole \ O_2}{2 \ moles \ Mg}$

→ $2.0\times 1$

→ $2.0 \ moles$

Thus the above  number of moles of oxygen gas is correct.

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