Question

directions: show all work for full credit and circle final answers.
use:
% element = (mass of element in formula / molar mass of compound) × 100

1. calculate the percent composition of each element in mgo.

Explanation:

Step1: Find molar masses of elements

Molar mass of Mg = 24.31 g/mol; O = 16.00 g/mol
Molar mass of MgO = 24.31 + 16.00 = 40.31 g/mol

Step2: Calculate % Mg

$\% \text{Mg} = \frac{24.31}{40.31} \times 100 \approx 60.3\%$

Step3: Calculate % O

$\% \text{O} = \frac{16.00}{40.31} \times 100 \approx 39.7\%$

Answer:

% Mg ≈ 60.3%, % O ≈ 39.7%