What is a molecule made up of?
- Assume 1 mol of the compound
- Find Molar Mass of each element in the compound
- Find the Molar Mass of the compound
- Multiply the Molar Mass of each element by the propotion (subscripts in the formula) of each element in the compound, divide by the Molar Mass of the compound then multiply by 100%
Ex. Find the % composition of AlCl
M_A$$_l = 26.982 g / mol M_C$$_l = 35.457 g / mol M_A$$_l$$_C$$_l$$_3 = 133.353 g / mol (total Molar Mass of 1 Aluminum and 3 Chlorine)
% Al = 26.982 g / mol (Molar mass of aluminum) * 1 (Representing how many Aluminums) * 100% / 133.353 g / mol (Total molar mass of the compound)
= 20.23% (composition of aluminum in the compound)
Homework (Grade 11 Chem)
p260 # 1 - 10 p262 # 1 - 8 p264 # 11 - 20 p266 # 21 - 30 p267 # 1 - 14