Answer: 1.2 moles
Step-by-step explanation:
Given that,
Amount of moles of Na2O (n) = ?
Mass of Na2O in grams = 75g
For molar mass of Na2O, use the atomic masses:
Sodium, Na = 23g;
Oxygen, O = 16g
Na2O = (23g x 2) + 16g
= 46g + 16g
= 62g/mol
Since, amount of moles = mass in grams / molar mass
n = 75g / 62g/mol
n = 1.2 moles
Thus, there are 1.2 moles are in 75g of Na20