if in ethanol, percentage composition is 45.45% of c, 23.40% of h, and 31.15% of o, which of the following…

if in ethanol, percentage composition is 45.45% of c, 23.40% of h, and 31.15% of o, which of the following is the number of relative moles of carbon present?\na 3.784 moles\nb 1.946 moles\nc 23.21 moles\nd none of the above

if in ethanol, percentage composition is 45.45% of c, 23.40% of h, and 31.15% of o, which of the following is the number of relative moles of carbon present?\na 3.784 moles\nb 1.946 moles\nc 23.21 moles\nd none of the above

Answer

Explanation:

Step1: Assume 100g of ethanol

We assume a 100 - g sample of ethanol so that the mass of carbon is 45.45g (since it is 45.45% of 100g).

Step2: Use molar - mass formula

The molar mass of carbon ($C$) is 12.01 g/mol. The number of moles ($n$) is calculated by the formula $n=\frac{m}{M}$, where $m$ is the mass and $M$ is the molar mass. So, $n_{C}=\frac{45.45g}{12.01g/mol}\approx3.784mol$.

Answer:

A. 3.784 moles