Question

a mixture has 18g of water and 414g of ethanol. calculate the mole fraction of water and ethanol.​

Answer 1

Answer:

18gm water i.e. 1 mole water

414gm ethanol i.e.5 mole ethanol

mole fraction of water=1÷1+5

=1/6

mole fraction of ethanol=5÷1+5

=5/6

Answer 2

Given :

• Weight of water = 18g
• weight of Ethanol = 414g

To find :

• mole fraction of H2O & Ethanol

Formula used :

• number of mole = weight ÷ molar mass
• mole fraction {a} = number of mole of a ÷ ( number of mole of a + Number of mole of b)

Molar mass :

• H2O = 18g/mol
• ethanol = 46 g/mol

Solution :

• moles of H2O = 18 ÷ 18
• moles of H2O = 1

• moles of Ethanol = 414 ÷ 46
• mole of Ethanol = 9

• mole fraction of H2O = mole of H2O ÷ (mole of H2O + mole of Ethanol)
• mole fraction of H2O = 1 ÷ (1+9)
• mole fraction of H2O = 1/10 = 0.1

• mole fraction of Ethanol = mole of Ethanol ÷ (mole of H2O+ mole of Ethanol)
• mole fraction of Ethanol = 9 ÷ (9+1)
• mole fraction of Ethanol = 9/10 = 0.9

AMSWER :

• mole fraction of H2O = 0.1
• mole fraction of Ethanol = 0.9