Answer:
The molarity of Z in this solution is 1.80 mol/L
Explanation:
29% (by mass) means that in 100 g of solution, you have 29 grams of solute.
So, by the solution density we can find our volume.
Density = mass / volume
Solution density = mass solution / volume solution
1.5 g/ml = 100 g / volume solution
volume solution = 100 g/ 1..5 g/ml
volume solution = 66.6 mL
So we have just found out that in 66.6 mL, we have 29 g of solute Z, so if we want to know the molarity, we have to find out the mass in 1 L, and afterwards, calculate the moles, we have
1000 mL = 1L
66.6 mL ____ 29 g of solute Z
1000 mL ____ (29 g . 1000 mL)/ 66.6 mL = 435.4 g
With the molar mass (formula weight), we can find out the moles
Mass /Molar mass = Mol
435.4 g /242 g/m = 1.80 mol
Molarity is 1.80 mol/L
