Question

calculate the molarity of a solution of ethanol in water in which the mole fraction of ethanol is 0.040

Answer 1

Explanation:

Take number of moles of water 55.55 gm

Then apply the formula of mole fraction and calculate the number of moles of C2H5OH.

Then calculate the molarity by letting the volume of solution 1l

Answer 2

moles of ethanol=0.04 mol

moles of water=1-0.04=0.96 mol

mass of ethanol=0.04 mol×46g/mol=1.84g

mass of water=0.96 mol×18g/mol=17.3g

mass of the solution=17.3g+1.84g=19.1g

density of water =1g/mol

volume of the solution=mass/density=19.1/1=19.1ml=0.0912

molarity of the solution=0.040/0.0191=2.1m