Question

an experiment using 4.65 grams of sodium sulfite, na₂so₃. what is the molar
119.06 g/mol
142.04 g/mol
126.04 g/mol
78.05 g/mol
clear all

Explanation:

Step1: Identify atomic masses

Atomic mass of Na: $22.99$ g/mol, S: $32.07$ g/mol, O: $16.00$ g/mol.

Step2: Calculate molar mass of $\ce{Na2SO4}$

Molar mass = $2\times22.99 + 32.07 + 4\times16.00$
= $45.98 + 32.07 + 64.00$
= $142.05$ g/mol (close to 142.04 g/mol due to rounding).

Answer:

142.04 g/mol (the option with 142.04 g/mol)