Question

calculate the mole fraction of ethanol and water in 25% ethanol solution by mass​

Answer 1

Answer:

Explanation:

Let the mass of solution is 100g

then, mass of water = 25g

mass of ethanol = 25g

mass of acetic acid = 50g

Now, find number of moles of each components ,

Number of mole of water = mass of water/Molar mass of water

= 25g/18g/mol [ ∵ molar mass of water = 18g/mol ]

≈ 1.4

Number of moles of ethanol = mass of ethanol/molar mass of ethanol

= 25g/46g/mol [ ∵ molar mass of ethanol (C2H5OH) = 46g/mol

= 0.54

Number of moles of acetic acid = mass of acetic acid/molar mass of acetic acid

= 50g/60g/mol [∵ molar mass of acetic acid (CH3COOH) = 60g/mol]

= 0.8

∴ total number of moles = 1.4 + 0.54 + 0.8 = 2.74

Now, mole fraction of water = moles of water/total moles

= 1.4/2.74 =0.51

similarly , mole fraction of ethanol = 0.54/2.74 = 0.197

mole fraction of acetic acid = 0.8/2.74 = 0.291