What is the mass of lithium oxide formed by the interaction of 35 grams of lithium with oxygen

Let’s write the reaction equation:

4Li + O2 = 2Li2O

Lithium Substance Amount:

v (Li) = m (Li) / M (Li) = 35/7 = 5 (mol).

According to the reaction equation, 2 mol of Li2O is formed per 4 mol of Li, therefore:

v (Li2O) = v (Li) * 2/4 = 5 * 2/4 = 2.5 (mol).

Thus, the mass of the formed lithium oxide is:

m (Li2O) = v (Li2O) * M (Li2O) = 2.5 * 30 = 75 (g).

Answer: 75 g.