Question

A solution was prepared by dissolving 5.76 g of KCl •MgCl2

Answer 1

a) (10.12 g salt) x [(1 mole salt)/(277.85 g salt)] x [(1)/(2.000 L soln)] = 0.0182 M  

b) (0.0182 M) x [(1 mole Mg2+)/(1 mole salt)] = 0.0182 M  

c) (0.0182 M) x [(3 moles Cl-)/(1 mole salt)] = 0.0546 M  

d) [(10.12 g salt)/(2000 mL)] x 100% = 0.506% (w/v)  

e) (0.0546 M Cl-)(25.0 mL soln) = 1.36 mmoles Cl-  

f) [(0.0182 moles K+) / (1.000 L)] x [(39.10 g K+)/(1 mole K+)] x [(1 L soln)/(1000 g soln)] x (1x10^6) = 712 ppm