Question

a sample of h2so4 is found to contain 1.05 g of h, 16.67 g of s, and 33.28 g of o. what is the percent composition of o in the compound? % o

Explanation:

Step1: Calculate the total mass of the compound

$$\begin{align*} \text{Total mass}&=\text{Mass of H}+\text{Mass of S}+\text{Mass of O}\\ &=1.05 + 16.67+33.28\\ &=51\space g \end{align*}$$

Step2: Calculate the percent composition of O

The formula for percent composition is $\text{Percent Composition}=\frac{\text{Mass of component}}{\text{Total mass of compound}}\times100\%$.
For O, $\text{Mass of component} = 33.28\space g$ and $\text{Total mass of compound}=51\space g$

$$\begin{align*} \text{Percent Composition of O}&=\frac{33.28}{51}\times 100\%\\ &= 0.6525\times100\%\\ &=65.25\% \end{align*}$$

Answer:

$65.25\%$