Question

What is the mass of 0.060 eq of NiAsO3 (with a molar mass of 182 g/mol) and how do you solve this?

Answer 1

It is salt of trivalent arsenite-anion AsO₃^3- and Ni³⁺ cation. In this case each mole of this salt represents to 3 equivalents (due to anion and cation valencies).
n = 3 * 0.060 eq = 0.180 mol
m = n MW = 0.180 mol * 182 g/mol = 32.76 g ≈ 32.8 g