Below you will find a variety of problems involving mole calculations.  These problems are best solved using dimensional analysis and then rounding your final answer to the correct number of significant figures.

Part 1:  Problems Involving Representative Particles

1.  Calculate the amount in moles in each of the following quantities.

a.  3.01 x 10²³ atoms of rubidium

b.  8.08 x 10²² atoms of krypton

2.  Calculate the number of atoms in each of the following amounts.

a.  1.004 mol bismuth

b.  2.5 mol manganese

3.  Calculate the number of molecules in each of the following amounts.

a.  4.99 mol of methane

b.  0.00520 mol of nitrogen gas

4.  Calculate the number of formula units in the following amounts.

a.  1.25 mol of potassium bromide

b.  5.00mol of magnesium chloride

5. Calculate the amount in moles of the following numbers of molecules or formula units.

a.  3.34 x 10²⁴ formula units of Cu(OH)₂

b.  1.17 x 10¹⁶ molecules of H₂S

Part 2:  Converting Between Moles and Grams

6.  Calculate the number of moles in each of the following masses.

a.  64.1g of aluminum

b.  28.1 g of silicon

7.  Calculate the mass of each of the following amounts.

a.  1.22 mol sodium

b.  14.5 mol copper

8.  Calculate the number of moles in each of the following masses.

a.  3.00 g of boron tribromide, BBr₃

b.  0.472 g of sodium fluoride, NaF

9.  Determine the mass of each of the following amounts.

a.  1.366 mol of NH₃

b.  0.120 mol of glucose, C₆H₁₂O₆

Part 3:  Problems with Multiple Conversion Factors

10.  Calculate the number of atoms in each of the following masses.

a.  54.0g of aluminum

b.  69.45g of lanthanum

11.  Calculate the mass of the following numbers of atoms.

a.  6.022 x 10²⁴ atoms of tantalum

b.  3.01 x 10²¹ atoms of cobalt

12.  Calculate the mass of each of the following quantities.

a.  2.41 x 10²⁴ molecules of hydrogen gas (remember that H is diatomic!)

b.  5.00 x 10²¹ formula units of aluminum hydroxide Al(OH)₃

13.  Calculate the number of molecules or formula units in each of the following masses.

a.  22.9 g of sodium sulfide Na₂S

b.  0.272 g of nickel (II) nitrate Ni(NO₃)₂

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