Answer: The percentage by mass of carbon in the given compound is 45.8 %
Step-by-step explanation:
We are given a chemical compound having chemical formula

To calculate the percentage composition of an element in a compound, we use the equation:

In 1 mole of given compound, 10 moles of carbon atoms are there.
Mass of
![C_(10)H_(14)N_2= [(10* 12)+(14 * 1)+(2* 14)]=262g/mol](https://img.qammunity.org/2017/formulas/chemistry/high-school/3c72smxqwx506ytyozj0dnlt63tv7ehzhp.png)
Mass of carbon element =
![[10* 12]=120g/mol](https://img.qammunity.org/2017/formulas/chemistry/high-school/y8uxodk0y7a1gcnixvxc05naohy2wk2l3g.png)
Putting values in above equation, we get:

Hence, percentage of carbon in given compound is 45.8 %.