Question

What is the mass in grams of 0.513 moles of Na2O?

Answer 1

No. of moles = Mass / Molar Mass

Moles = 0.513 moles

Molar mass of Na2O = 23 × 2 + 16 = 62 g.

$0.513 = \frac{mass}{62}$

$mass = 0.513 \times 62 = 31.806 \: g$

Therefore, the mass of Na2O is 31.806 g .

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