Question

How many moles of each component are present in a solution containing 28.0 g methanol and 55.0 g ethanol?

a) Methanol: 0.875 moles, Ethanol: 1.083 moles
b) Methanol: 1.750 moles, Ethanol: 2.167 moles
c) Methanol: 2.000 moles, Ethanol: 3.000 moles
d) Methanol: 3.000 moles, Ethanol: 2.000 moles

Answer 1

The solution contains 0.873 moles of methanol (CH3OH) and 1.193 moles of ethanol (C2H5OH), which rounds off to 0.875 and 1.193 respectively. The closest corresponding answer choice is a) Methanol: 0.875 moles, Ethanol: 1.083 moles.

Step-by-step explanation:

To calculate the number of moles of methanol and ethanol in the solution, we first need to identify the molecular formulas and molar masses of methanol (CH3OH) and ethanol (C2H5OH). Methanol has a molar mass of approximately 32.04 g/mol and ethanol has a molar mass of approximately 46.07 g/mol.

We use the formula: number of moles = mass (in g) ÷ molar mass (g/mol) to calculate the moles of each component:

• For methanol: 28.0 g CH3OH ÷ 32.04 g/mol = 0.873 moles of methanol
• For ethanol: 55.0 g C2H5OH ÷ 46.07 g/mol = 1.193 moles of ethanol

Therefore, the solution contains 0.873 moles of methanol and 1.193 moles of ethanol. The closest answer choice to our calculations is a) Methanol: 0.875 moles, Ethanol: 1.083 moles, although the value for ethanol has been rounded down slightly from the calculated value of 1.193 moles.