Question

How many grams of Cl are in 495 g of CaCl2

Answer 1

What is the atomic mass of calcium and the atomic mass of chlorine?

Answer 2

atomic mass of Ca=20 & Cl=35.5

Answer 3

Okay, if the atomic mass of Ca = 20 g/mol and Cl = 35.5 g/mol, 1 mole of CaCl2 will have a molar mass of the sum of the atomic masses of the numbers of atoms of each type required to make a molecule of CaCl2.

If you multiply the mass of CaCl2 by the fraction of the molar mass of CaCl2 that is due to Cl atoms, you'll have your answer. Each molecule of CaCl2 has 1 Ca atom and 2 Cl atoms, so that fraction should be

2*<molar mass Cl>
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2*<molar mass Cl> + 1*<molar mass Ca>