Calculate the mole fraction of ethylene glacol `(C_(2)H_(6)O_(2))` in a solution containing 20% of ethylene glycol by mass.

Explanation

To calculate the mole fraction of ethylene glycol (C₂H₆O₂) in a solution containing 20% ethylene glycol by mass, follow these steps:

### Step 1: Understand the Mass Percentage
The solution contains 20% ethylene glycol by mass. This means that in 100 grams of the solution, there are 20 grams of ethylene glycol and 80 grams of solvent (water).

### Step 2: Calculate the Number of Moles of Ethylene Glycol
To find the number of moles of ethylene glycol, we need its molar mass. The molar mass of ethylene glycol (C₂H₆O₂) can be calculated as follows:
- Carbon (C): 12 g/mol × 2 = 24 g/mol
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