Calculate the moles of O atoms in 0.603g of Ca(NO3)2. Round your answer to 3 significant figures.

Answer 1

Recognize that each mole of Ca(NO₃)₂ contains 1 mole of Ca, 2 moles of N, and 6 moles of O. So, we will calculate the moles of Ca(NO₃)₂ in 0.603 g, and then multiply that value by 6 to get moles of O.

molar mass Ca(NO₃)₂ = 164.1 g / mol

0.603 g Ca(NO₃)₂ x 1 mol / 164.1 g = 3.675x10^-3 moles Ca(NO₃)₂

3.675x10^-3 moles Ca(NO₃)₂ x 6 mols O atoms / mol Ca(NO₃)₂= 0.0220 moles of O atoms (3 sig.figs.)