Lithium weighing 3.5 g was burned in oxygen. Calculate the mass of lithium oxide formed in this process.

2Li + O2 = Li2O
m (lithium oxide) = 0.5n (lithium) * M (lithium oxide) = 0.5 * (3.5 / 7) * (7 * 2 + 16) = 7.5 g
Answer: 7.5 g

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