Question

A solution is made up of 150g of disodium phosphate. Na2HPO4.7H20,dissolved in 2500g of water. what is the molality of the solution?


1) 0.107m
2)0.224m
3)2.365m
4)2.679

Answer 1

Molality=molessolute/kgwater=(150/molemass)/2.5

so count up the atomic mass of the disodium phosphate.