J.R. S. answered 10/24/21
Ph.D. University Professor with 10+ years Tutoring Experience
3H2SO4(aq) + 2Al(s) ==> Al2(SO4)3 + 3H2(g) ... balanced equation
moles H2SO4 present = 450 ml x 1 L / 1000 ml x 0.85 mol/L = 0.3825 mols H2SO4
mass Al2(SO4)3 produced = 0.3825 mol H2SO4 x 1 mol Al2(SO4)3 / 3 mol H2SO4 x 342 g/mol = 43.6 g Al2(SO4)3 = 44 g Al2(SO4)3 (to 2 sig. figs.)