IGCSE – THE MOLE – CLASSWORK
IMPORTANT: SHOW YOUR WORK USING WITH PROPORTIONS OR DIMENSIONAL ANALYSIS
A-Calculate the following molar masses:
- Copper (II) Nitrate. Cu(NO3)2
- Dinitrogen trioxide – N2O3
- Phosphoric acid. H3PO4
- Potassium Sulfate. K2SO4
- Epson Salts (MgSO4•7H2O)
B-Calculate the mass in grams contained in the quantities specified:
- 3 moles of sulfur – S
- 2 moles of silicon – Si
- 0.01 moles of lead (II) iodide. – PbI2
- 20 moles of hydrochloric acid – HCl
- 0.1 moles of Cobalt(II) Chloride hexahydrate (CoCl2•6H2O)
C-Calculate the moles contained in the following masses
- 4 g of sodium hydroxide – NaOH
- 8 g of water – H2O
- 585 g of sodium chloride NaCl
- 64 g of methane gas CH4
- 25 g of Copper sulfate pentahydrate (CuSO4•5H2O)
D-Calculate the number of particles specified in the following exercises:
- Atoms in 1.2 g of C
- Atoms in 320 g of O
- Molecules in 7.1 of Cl2
- Molecules in 54 g of H2O
- Molecules in 29.4 g of H3PO4
ANSWERS:
Calculate the following molar masses:
- Ans: 188
- Ans: 76
- Ans: 98
- Ans: 174
- Ans: 246
Calculate the mass in grams contained in the quantities specified:
- Ans: 96g
- Ans: 56g
- Ans: 4.61g
- Ans: 730g
- Ans: 23.8g
Calculate the moles contained in the following masses
- Ans: 0.1 mol
- Ans: 0.44 mol
- Ans: 10 mol
- Ans: 4 mol
- Ans: 0.1 mol
Calculate the number of particles specified in the following exercises:
- Ans: 6.022 × 1022 atoms
- Ans: 1.204 × 1025 atoms
- Ans: 6.022 × 1022 molecules
- Ans: 1.806× 1024 molecules
- Ans: 1.806 × 1023 atoms