Calculate the mass ratio of zinc to iodine in zinc iodide. (mass of zinc consumed is 1.05g and mass of iodine consumed is 1.98g) Mass of ZnI2 after reaction is 2.45g?

The mass ratio of zinc to iodine in zinc iodide is 0.25755. Below is the solution.

Solution:

molar mass of zinc iodide = 319.22 g/mole

zinc = 1 (atom) x 65.38 g/mole = 65.38 g/mole

iodine = 2 (atoms) x 126.92 g/mole = 253.84 g/mole

[ (65.38 g/mole) / (319.22 g/mole) ] x 100 % = 20.48 %

0.50176 g / 1.94824 g = 0.2575452716 or 0.25755