what is the molarity of the following?

Question

a) 0.96 g MgCl2 in 500 mL of solution
b) 9.33 g Na2S in 450 mL solution
c) 2.48 g CaF2 in 375 mL of solution

Answer 1

ill get u started. M=moles/Liters. change grams to moles by dividing by the molar mass. then divide by the LITERS(i emphasize Liters, not mL) change mL to liters by dividing by 1000.

Answer 2

Atomic weights: Mg=24 Cl=35.5 MgCl2=95 Na=23 S=32 Na2S=78 Ca=40 F=19 CaF2=78

a) 0.96gMgCl2/500mL x 1molMgCl2/95gMgCl2 x 1000mL/1L = 0.02molMgCl2/1L = 0.02M

b)9.33gNa2S/450mL x 1molNa2S/78gNa2S x 1000mL/1L = 0.27molNa2S/1L = 0.27M

c) 2.48gCaF2/375mL x 1molCaF2/78gCaF2 x 1000mL/1L = 0.08molCaF2/1L = 0.08M