Laws of Chemical Combination + Percentage Composition | SS1 Chemistry Week 6

Welcome to Science with Mrs. Okpe. In this SS1 Chemistry Week 6 lesson, we study the Laws of Chemical Combination and learn how mass relationships help us understand chemical reactions and compounds. In this lesson, you will learn: • How to calculate molar mass from a chemical formula • How to calculate percentage composition by mass • The Law of Conservation of Mass • Why atoms are rearranged but not created or destroyed during a chemical reaction • How to solve missing-mass questions using conservation of mass • The Law of Definite Proportions • How water demonstrates a fixed mass ratio of hydrogen to oxygen • The Law of Multiple Proportions • How carbon monoxide (CO) and carbon dioxide (CO₂) illustrate multiple proportions • Step-by-step worked examples and revision questions Worked examples include: NaNO₃ percentage composition CaCO₃ molar mass Formation of water Heating of CaCO₃ Missing product mass H₂O and definite proportions CO and CO₂ and multiple proportions This lesson is suitable for SS1 Chemistry students following the Nigerian secondary-school Chemistry curriculum and is useful for classroom learning, revision, tests and examination preparation. Subscribe to Science with Mrs. Okpe for more clear and engaging Chemistry lessons. #SS1Chemistry #LawsOfChemicalCombination #PercentageComposition #ChemistryMadeEasy #ScienceWithMrsOkpe