To find the molecular mass of sodium oxide [tex]\(\text{Na}_2\text{O}\)[/tex]:
1. Identify the atomic masses:
- Sodium (Na): The atomic mass of sodium is 22.98977 g/mol.
- Oxygen (O): The atomic mass of oxygen is 15.999 g/mol.
2. Determine the molecular formula:
- Sodium oxide has the chemical formula [tex]\(\text{Na}_2\text{O}\)[/tex], which means it contains 2 sodium (Na) atoms and 1 oxygen (O) atom.
3. Calculate the molecular mass:
- The molecular mass of sodium oxide is obtained by summing the masses of all the atoms present in the molecule.
Step-by-step calculations:
- Mass contribution from sodium: [tex]\(2 \times 22.98977 \, \text{g/mol}\)[/tex]
[tex]\[ 2 \times 22.98977 = 45.97954 \, \text{g/mol} \][/tex]
- Mass contribution from oxygen: [tex]\(1 \times 15.999 \, \text{g/mol}\)[/tex]
[tex]\[ 15.999 \, \text{g/mol} \][/tex]
4. Add the masses together:
[tex]\[ 45.97954 \, \text{g/mol} + 15.999 \, \text{g/mol} = 61.97854 \, \text{g/mol} \][/tex]
Hence, the molecular mass of [tex]\(\text{Na}_2\text{O}\)[/tex] is:
[tex]\[ 61.97854 \, \text{g/mol} \][/tex]
Therefore, the correct answer is:
B. 61.97854
