Reaction equation: 4Na + O2 = 2Na2O
According to the periodic table, we determine the molar mass of sodium M = 23 g / mol. And sodium oxide M = 23 * 2 + 16 = 62 g / mol.
Let’s find the amount of sodium oxide substance: n = m / M = 3.1 g / 62 g / mol = 0.05 mol.
According to the reaction equation, from 4 mol of sodium, 2 mol of sodium oxide is obtained, which means n (Na) / 4 = 0.05 / 2. Hence n (Na) = 4 * 0.05 / 2 = 0.1 mol.
Find the mass of sodium: m = n * M = 0.1 mol * 23 g / mol = 2.3 g.
Answer: the mass of sodium is 2.3 g.
One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.