Question

6 mark for review a 23.0g sample of a compound contains 12.0g of c, 3.0g of h, and 8.0g of o. which of the following is the empirical formula of the compound? a ch3o b c2h6o c c3h9o2 d c4h12o2

Explanation:

Step1: Calculate the number of moles of each element

• Moles of \(C\): \(n_{C}=\frac{12.0\ g}{12.0\ g/mol}=1\ mol\)
• Moles of \(H\): \(n_{H}=\frac{3.0\ g}{1.0\ g/mol}=3\ mol\)
• Moles of \(O\): \(n_{O}=\frac{8.0\ g}{16.0\ g/mol}=0.5\ mol\)

Step2: Divide each mole value by the smallest mole value

• Divide by \(0.5\)
• For \(C\): \(\frac{1\ mol}{0.5\ mol} = 2\)
• For \(H\): \(\frac{3\ mol}{0.5\ mol}=6\)
• For \(O\): \(\frac{0.5\ mol}{0.5\ mol}=1\)

Answer:

B. \(C_{2}H_{6}O\)