What is the molar mass of sodium carbonate (Na₂CO₃)? Your answer should be rounded to the nearest whole number. Do not include units in your answer.
The Correct Answer and Explanation is:
To calculate the molar mass of sodium carbonate (Na₂CO₃), we need to determine the sum of the atomic masses of all the atoms present in one molecule of sodium carbonate.
Step-by-Step Calculation:
- Atomic Mass of Sodium (Na): The atomic mass of sodium is approximately 23.0 grams per mole. Since there are two sodium atoms in Na₂CO₃, we multiply the atomic mass of sodium by 2:
[
23.0 \, \text{g/mol} \times 2 = 46.0 \, \text{g/mol}
] - Atomic Mass of Carbon (C): The atomic mass of carbon is approximately 12.0 grams per mole. Since there is one carbon atom in Na₂CO₃, the contribution from carbon is:
[
12.0 \, \text{g/mol} \times 1 = 12.0 \, \text{g/mol}
] - Atomic Mass of Oxygen (O): The atomic mass of oxygen is approximately 16.0 grams per mole. Since there are three oxygen atoms in Na₂CO₃, we multiply the atomic mass of oxygen by 3:
[
16.0 \, \text{g/mol} \times 3 = 48.0 \, \text{g/mol}
]
Total Molar Mass:
Now, we add the contributions from sodium, carbon, and oxygen:
[
46.0 \, \text{g/mol} (\text{from Na}) + 12.0 \, \text{g/mol} (\text{from C}) + 48.0 \, \text{g/mol} (\text{from O}) = 106.0 \, \text{g/mol}
]
Conclusion:
The molar mass of sodium carbonate (Na₂CO₃) is approximately 106 grams per mole when rounded to the nearest whole number. This calculation is important for determining the amount of substance in moles, which is crucial in stoichiometric calculations and understanding the quantities of reactants and products in chemical reactions.