# A sample of C_3H_8 has 8.48x10^24 H atoms. How many carbon atoms does the sample contain?

For every $\text{8 hydrogens}$ in propane there are $\text{3 carbons}$.
And thus if there are $8.48 \times {10}^{24}$ hydrogen atoms, there are $\frac{3}{8} \times 8.48 \times {10}^{24}$ carbon atoms, approx. $3 \times {10}^{24}$ carbon atoms. What is the mass of this quantity of carbon atoms?