Sodium Nitrate, NaNO3 Formula = number of atoms x atomic weight Sodium Nitrate, NaNO3 (Na = 23.0 g/mol; N = 14.0 g/mol; O = 16.0 g/mol) Mass of Na = x 23.0 g/mol g/mol Mass of N = x 14.0 g/mol g/mol Mass of O = x 16.0 g/mol g/mol Molar mass of Sodium Nitrate, NaNO3 = g/mol
The Correct Answer and Explanation is:
To calculate the molar mass of Sodium Nitrate (NaNO₃), we use its chemical formula and the atomic weights of the elements involved:
Step-by-step calculation:
- Na (Sodium): 1 atom × 23.0 g/mol = 23.0 g/mol
- N (Nitrogen): 1 atom × 14.0 g/mol = 14.0 g/mol
- O (Oxygen): 3 atoms × 16.0 g/mol = 48.0 g/mol
Total molar mass:
Molar mass of NaNO₃ = 23.0 + 14.0 + 48.0 = 85.0 g/mol
explanation:
Sodium nitrate (NaNO₃) is an ionic compound made up of one sodium ion (Na⁺) and one nitrate ion (NO₃⁻). To determine the molar mass of sodium nitrate, we must sum the atomic masses of all the atoms present in one formula unit of the compound. The atomic mass is the weighted average mass of the atoms of an element, expressed in grams per mole.
The compound contains three types of atoms: sodium (Na), nitrogen (N), and oxygen (O). According to the atomic weights provided, sodium has a mass of 23.0 grams per mole, nitrogen has a mass of 14.0 grams per mole, and oxygen has a mass of 16.0 grams per mole.
Each unit of sodium nitrate has:
- One sodium atom, contributing 23.0 g/mol,
- One nitrogen atom, contributing 14.0 g/mol,
- Three oxygen atoms, each contributing 16.0 g/mol, for a total of 48.0 g/mol from oxygen.
When we add these values together — 23.0 + 14.0 + 48.0 — we get a total molar mass of 85.0 g/mol. This value tells us that one mole of sodium nitrate weighs 85.0 grams. Molar mass is an essential property used in stoichiometric calculations in chemistry because it connects the microscopic scale of atoms and molecules to the macroscopic scale of grams and liters used in the laboratory.
