Question

What is the molarity of solution that contains 5.80 grams of nickel nitrate,ni(no3)2 in 500.ml?

Answer 1

Molarity is defined as the number of moles of solute in 1 L of solution 
molar mass of Ni(NO₃)₂ - 182.7 g/mol
number of moles of Ni(NO₃)₂ - 5.80 g/ 182.7 g/mol = 0.0317 mol
number of moles in 500 mL - 0.0317 mol
therefore number of moles in 1000 mL - 0.0317 mol / 500 mL x 1000 mL/L 
molarity of the solution is - 0.0634 M