Question

how many moles are there in 10.0g of C2H5OH? (SHOW YOUR WORK)

Answer 1

Question

How many moles are there in $10.0\mathrm{g}$ of $\mathrm{C}_2\mathrm{H}_5\mathrm{OH}$?

Solution:

Number of moles equals:

$$n = \frac {m}{M}$$

m – Mass of $\mathrm{C}_2\mathrm{H}_5\mathrm{OH}$, m = 10.0 g.

M – Molar mass of $\mathrm{C}_2\mathrm{H}_5\mathrm{OH}$, equals:

$$M = 2 M (C) + 6 M (H) + M (O) = 2 \cdot 12 + 6 \cdot 1 + 16 = 46 \frac {g}{mole}$$

Then number of moles in $10.0\mathrm{g}$ of $\mathrm{C}_2\mathrm{H}_5\mathrm{OH}$ equals:

$$n = \frac {10}{46} = 0.217 \text{ moles}$$

Answer: $n = 0.217$ moles.