chemistry question!!? help?

Question

Please tell me step by step nd the actual answer..thanks

Q:An antifreeze (aq) solution is 40.0% ethylene glycol (C2H602) by mass. The density of the solution is 1.05 g/cm3. Calculate the molality, molartiy, and mole fraction of the ethylene glycol.

help me~!!!

Answer 1

Molality = moles of ethyleneglycol/Kg of solution

Take a base of 1 Kg of solution, then a mass (m) of 400 gr are ethyleneglycol (EG) and the rest is water (600gr). Investigate the molecular weight (MW) of ethyleneglycol (wikipedia.org may help)

Now calculate the moles (n) of EG

n=m/MW

divide this result by 1 and voilá, molality

Now, calculate the volume ocuppied by this kilogram of solution. Density is 1.05 g/cm3 or Kg/L. So, divide 1Kg by 1.05 Kg/L and you will obtain the volume (V) of solution in L. Now calculate the molarity (M)using the followin eq.

Molarity = moles/volume of solution (in L)

M=n/V

To calculcate the mole fraction consider:

Total number of moles=Moles of EG +moles of water.

You already calculated the moles of EG in one kilogram of solution. Now calculate the moles of water, dividing its mass (600 g) by its MW (That is 18) and then make the sum above to determine the total number of moels

Finally divide moles of EG by Total number of moles to obtain the mole fraction


I know I might not be very popular, but I won't tell you the actual result because I am not the one who solves anybodyelse's homework. think about it, it would not be ethical. Try to finish it yourself, What do you go to school if you get the homework from someone else and don't learn? Rather pick up a shovel and start a career in construction or something