Carbon occurs in nature as a mixture of ${ }^{12} \mathrm{C}$ and ${ }^{13} \mathrm{C}$. The average

Question

Carbon occurs in nature as a mixture of ${ }^{12} \mathrm{C}$ and ${ }^{13} \mathrm{C}$. The average atomic mass of carbon is 12.011 . What is the % abundance of ${ }^{12} \mathrm{C}$ in nature?\

Professor PC Thomas Classes · Answer

(b) : Let % abundance of ${ }^{12} \mathrm{C}=x$\ $\%$ abundance of ${ }^{13} \mathrm{C}=100-x$ $$ \begin{aligned} \because \quad \frac{12 x}{100}+\frac{13(100-x)}{100} & =12.011 \ 12 x+1300-13 x & =1201.1 \Rightarrow x=98.9 \end{aligned} $$ Thus, % abundance of ${ }^{12} \mathrm{C}$ is $98.9 \%$.\