Aqueous magnesium chloride solution is marketed as 20% by mass. Its density is 1.18 g/ml. Calculate (i) The mole fraction of each component(ii)Molarity (iii)Molality (iv) The concentration in ppm

Aqueous magnesium chloride solution is marketed as 20% by mass. Its de

1.	Aqueous magnesium chloride solution is marketed as 20% by mass. Its density is 1.18 g/ml. Calculate (i) The mole fraction of each component(ii)Molarity (iii)Molality (iv) The concentration in ppm
Answer» tion:As you know, a 1.75-mol L−1 hydrochloric ACID solution will contain 1.75 moles of hydrochloric acid, the solute, for every 1 L of solution.So right from the start, you know that your solution must contain 1.75moles of hydrochloric acid.Use the COMPOUND's MOLAR mass to CONVERT this to grams 1.75moles HCl.36.46 g1mole HCl=63.805 G Now, you know that your stock solution is 36.0% hydrochloric acid by mass, which implies that in order to have 36.0 g of hydrochloric acid, you need 100 g of this solution.You can thus say that in order for your target solution to contain 63.805 g of hydrochloric acid, the sample you take from the stock solution must have a mass of63.805g HCl⋅100 g solution36.0g HCl=177.24 g Use the density of the stock solution to figure out the volume of the sample177.24g solution⋅1 mL1.18g solution=209 mL−−−−−−example hope