Answer:
223.5 g
Explanation:
The formula between the number of moles, mass and Mr can be used to convert moles to grams.
Number of moles = mass ÷ Mr
So, mass = number of moles × Mr
Mr of Li₂O = (6.9 × 2) + 16 = 29.8
∴ Mass = 7.5 × 29.8 = 223.5 g
