Question

calculate the molarity of the solution of Ethanol in water in which the mole fraction of Ethanol is 0.040 and density of water is 1

Answer 1

Answer

Mole fraction of C2H5OH=................1

Let the moles of C2H5OH= X

Now density of water = 1 (given)

And the weight of 1000ml of water = volume * density (from density = mass/volume)

= 1000 x 1=1000g

Therefore moles of water = 1000/18= 55.55 mol (18g is molecular mass of water)

Also mole fraction of C2H5OH= 0.040 (given)

Putting the values in equation 1,we get

=0.040=X/X+55.55

=0.040X+2.222 = X

OR X= 2.3145 mol

Molarity of solution = 2.314 M