Molar Mass and Formula Mass Calculations

Front

What is Molar Mass?

Back

The mass of one mole of a substance, typically expressed in grams per mole (g/mol).

Front

How do you calculate Molar Mass?

Back

Add the atomic masses of all atoms in the chemical formula of the substance.

Front

What is the formula for Aluminum Chloride?

Back

AlCl₃.

Tags

NGSS.MS-PS1-1

Front

Calculate the Molar Mass of Aluminum Chloride (AlCl₃).

Back

133.341 g/mol.

Front

What is an Empirical Formula?

Back

The simplest whole-number ratio of atoms of each element in a compound.

Front

How do you find the Empirical Formula from percentages?

Back

Convert percentages to grams, then to moles, and simplify the mole ratio.

Front

What is the Empirical Formula for 40.05% S and 59.95% O?

Back

SO₃.

Front

What is the formula for Cobalt(II) Chloride Dihydrate?

Back

CoCl₂•2H₂O.

Front

How do you calculate percent by mass of water in a hydrate?

Back

(Mass of water / Mass of hydrate) x 100.

Front

Calculate the percent water by mass in CoCl₂•2H₂O.

Back

21.7%.