Question

question 10 (1 point) what is the percentage, by mass, of oxygen in the compound u3o8? (note: u, 238 g/mol, o 16 g/mol) 15.2 % 17.9 % 30.4 % 35.0 % 72.7 %

Explanation:

Step1: Calculate molar mass of U₃O₈

The molar mass of U is 238 g/mol and of O is 16 g/mol. For U₃O₈, molar - mass of U₃ = 3×238 = 714 g/mol, molar - mass of O₈ = 8×16 = 128 g/mol. So, molar mass of U₃O₈ = 714+128 = 842 g/mol.

Step2: Calculate mass percentage of O

Mass percentage of O=$\frac{\text{Mass of O in U₃O₈}}{\text{Molar mass of U₃O₈}}\times100\%=\frac{128}{842}\times100\%\approx15.2\%$

Answer:

15.2%