Question

Find the formula mass of the compound, then divide the individual element total by the total mass-move the decimal over two to change it to percentage C2H5NBr

Answer 1

Find the molar massesof each element in the periodic table:

`\begin{gathered} C=12g*2=24g \\ H=1g*5=5g \\ N=14g*1=14g \\ Br=80g*1=80g \\ C_2H_5NBr=123g \end{gathered}`

Divide each mass by the total mass to find the percentage mass of each element:

`\begin{gathered} C=(24g)/(123g)=0.195=19.5\% \\ H=(5g)/(123g)=0.041=4.1\% \\ N=(14g)/(123g)=0.114=11.4\% \\ Br=(80g)/(123g)=0.65=65\% \end{gathered}`