Question

the sample contains 0.624 mol c, 1.248 mol h, and 0.078 mol o. determine the empirical formula for the hydrocarbon. what is the subscript for h? c₈h?o

Explanation:

Step1: Find the ratio of moles of C to the given subscript of C

The subscript of C is 8, and the moles of C is 0.624 mol. Let the ratio factor be \( r \), so \( r=\frac{8}{0.624} \).

Step2: Calculate the ratio factor

\( r = \frac{8}{0.624}\approx12.82 \) (approximate value, but we can also use the ratio of moles of H to moles of C and then multiply by subscript of C). Alternatively, find the mole ratio of H to C first. The mole ratio of H to C is \( \frac{1.248}{0.624}=2 \). So for each C atom, there are 2 H atoms. Since there are 8 C atoms, the number of H atoms is \( 8\times2 = 16 \). Let's verify with the ratio factor. Moles of H is 1.248 mol. Multiply moles of H by the ratio factor \( r=\frac{8}{0.624} \). So \( 1.248\times\frac{8}{0.624}=\frac{1.248\times8}{0.624}=\frac{9.984}{0.624} = 16 \).

Answer:

16