J.R. S. answered 02/05/21
Ph.D. University Professor with 10+ years Tutoring Experience
What's the question? Are you asking for the molarity of the solution?
molar mass Al(NO3)3 = 212.99 g/mol
54.20 g x 1 mol / 212.99 g = 0.2545 moles
molarity = moles / liter
molarity (M) = 0.2545 moles / 1.500 L = 0.1696 M = 0.17 M (2 sig. figs. based on 1500 ml having 2 s.f.)