Question

9. Determine the percent compositions for each of the following compounds. a. Ba(OH)2

Answer 1

`\begin{gathered} Ba=80.14\% \\ O_2=18.67\% \\ H_2=1.18\% \end{gathered}`

Explanations:

In order to find the percent composition by mass of each element, you will follow the following step:

Step 1: Determine the molar mass of Ba(OH)2

`\begin{gathered} Ba(OH)_2=137.327+2(16)+(2.016) \\ Ba(OH)_2=137.327+32+2.016 \\ molar\text{ mass of Ba\lparen OH\rparen}_2=171.359gmol^(-1) \end{gathered}`

Step 2: Determine the composition by mass of each element

For Barium element

`\begin{gathered} \%Ba=(137.327)/(171.359)*100\% \\ \%Ba=0.8014*100 \\ \%Ba=80.14\% \end{gathered}`

For Oxygen element

`\begin{gathered} \%O=(32)/(171.359)*100 \\ \%O=0.1867*100 \\ \%O=18.67\% \end{gathered}`

For the oxygen element

`\begin{gathered} \%H=(2.016)/(171.359)*100 \\ \%H=0.0118*100 \\ \%H=1.18\% \end{gathered}`