Mole Review

Mole Concepts

100

Avogadro's Number 

6.02 x 10²³ 

200

1 mole of lead (Pb) has this mass and number of atoms 

207.2 g and 6.02x10²³ atoms

300

Who came up with the concept of the mole?

Amadeo Avogadro

400

If you start with grams but need moles what do you do? 

Grams divided by (molar mass) grams 

500

If you start with particles and need moles, what do you do?

Particles divided by Avogadro's # to find moles

Gram to Mole Conversions

100

How many moles are in 79.85 g of Fe₂O₃?

Molar mass Fe₂O₃ = 159.7 g/mol

79.85 g / 159.7 g/mol = 0.5 mol

200

How many moles are in 1086 g of Ca₃(PO₄)₂? (The molar mass of Ca₃(PO₄)₂ is 310.8 g/mol)

1085.63 g /310.18 g/mol   = 3.5 mol

300

How many moles are in 85 g of AgNO₃? 

Molar mass = 169.88 g/mol

85g / 169.88 g/mol = 0.5 mol AgNO₃

400

How many moles are in 62.5 g of sodium sulfate? 

.440 mol Na₂SO₄

500

How many moles are in 22 grams of H₂O?

1.2 mol H₂O

Mole to Gram Conversions

100

Uranium (molar mass = 283.03 g/mol) has the largest molar mass of any element naturally found on Earth.

What is the mass (grams) of 7.50 mol of uranium?

7.5 mol x 238.03 g/mol = 2122 g

200

How many grams are in 23 moles of carbon?

23 mol X 12.01 g/mol = 276.23 g

300

How many grams are in 5 moles of NH₃? (The molar mass of NH₃ is 17 g/mol.)

5 mol x 17 g/mol = 85 g

400

How many grams are in 133.45 mol of SO2?

133.45 mol x 64.07 g/mol =8550 g

500

How many grams are in 3.996 mol of C₆H₁₂O₆? (Hint--find the molar mass first!)

3.996 mol X 180.18 g/mol = 720 g

Molar Mass

100

What is the molar mass of HCl? 

Molar mass HCl = 36.46 g/mol

200

What is the molar mass of H₂CO₃? 

Molar mass = 62.03 g/mol

300

What is the molar mass of LiBr?

Molar mass = 86.84 g/mol

400

What is the molar mass of C₆H₁₂O₆?

Molar mass = 180.18 g/mol

500

What is the molar mass of Ca(OH)₂?

74 g/mol