Question

Determine the percentage by mass of each element in the following compounds. (Round your answers to one decimal place.)(a)milk of magnesia, Mg(OH)2Mg:____%O:______%H:______%(b)lye, NaOHNa:____%O:_____%H:_____%

Answer 1

Firstly we will calculate the mass of the molecule by adding the together the atomic mass of each element:

`\begin{gathered} Mg:24.31g \\ O:16.00g \\ H:1.00g \\ _mMg(OH)_2=24.31+(16.00*2)+(1.01*2) \\ _mMg(OH)_2=58.33gmol^(-1) \\ \\ \\ Na:22.99g \\ O:16.00g \\ H:1.01g \\ _mNaOH=22.99+16.00+1.01 \\ _mNaOH=40gmol^(-1) \end{gathered}`

Now we will determine the percentage mass of each of element: