Question

. Вычислите относительную молекулярную массу карбоната натрия, определите массовую долю кислорода в данном веществе

Answer 1

Calculation of the Relative Molecular Mass of Sodium Carbonate

To calculate the relative molecular mass of sodium carbonate (Na2CO3), we need to consider the atomic masses of each element present in the compound.

The atomic masses of the elements are as follows: - Sodium (Na): 22.99 g/mol - Carbon (C): 12.01 g/mol - Oxygen (O): 16.00 g/mol

The molecular formula of sodium carbonate is Na2CO3, which means it contains two sodium atoms, one carbon atom, and three oxygen atoms.

To calculate the relative molecular mass, we add up the atomic masses of each element in the compound: Relative Molecular Mass of Na2CO3 = (2 * Na) + C + (3 * O)

Substituting the atomic masses: Relative Molecular Mass of Na2CO3 = (2 * 22.99) + 12.01 + (3 * 16.00)

Calculating the values: Relative Molecular Mass of Na2CO3 = 45.98 + 12.01 + 48.00 Relative Molecular Mass of Na2CO3 = 105.99 g/mol

Therefore, the relative molecular mass of sodium carbonate (Na2CO3) is 105.99 g/mol.

Calculation of the Mass Fraction of Oxygen in Sodium Carbonate

To determine the mass fraction of oxygen in sodium carbonate (Na2CO3), we need to calculate the mass of oxygen in the compound and divide it by the total mass of the compound.

The molecular formula of sodium carbonate is Na2CO3, which means it contains three oxygen atoms.

To calculate the mass fraction of oxygen, we need to know the molar mass of sodium carbonate, which we calculated earlier as 105.99 g/mol.

The molar mass of oxygen is 16.00 g/mol.

To calculate the mass of oxygen in sodium carbonate, we multiply the molar mass of oxygen by the number of oxygen atoms in the compound: Mass of oxygen in Na2CO3 = (3 * 16.00)

Calculating the value: Mass of oxygen in Na2CO3 = 48.00 g/mol

To calculate the mass fraction of oxygen, we divide the mass of oxygen by the total mass of sodium carbonate: Mass fraction of oxygen = (Mass of oxygen in Na2CO3) / (Relative Molecular Mass of Na2CO3)

Substituting the values: Mass fraction of oxygen = 48.00 / 105.99

Calculating the value: Mass fraction of oxygen = 0.452 or 45.2%

Therefore, the mass fraction of oxygen in sodium carbonate (Na2CO3) is approximately 45.2%.