Question

6.44 * 10^-2 kg of hydrated sodium sulphate (Na2SO4.xH2O) is dissolved in water to obtain a 1 dm^3 solution. If the molarity of the solution with respect to Na2So4 is 0.2 M then what is the value of x?

Answer 1

Answer:

Answer:

10

Explanation:

Given data:

wight of na2so4.xh2o--> 6.44 * 10^-2 kg

wight of solvent--> 1ml

Formula required : Molarity = weight of solute/molecular weight of solute*1000/vol. of solvent(ml)

Sub:

0.2= 6.44 * 10^-2 /mw *1000/1

--> molecular wt of solute =322kg

so if u take 10 moles h2o --you will get 322 kg of na2so4.10h2o (142+180=322)