ACSI 2022 HL Notes Stoichiometric Relationships (Teacher)

IBDP Chemistry HL/Stoichiometric Relationships Page 1 Anglo − Chinese School (Independent) Year 5 (2022) IBDP Chemistry HL (IB DP syllabus Topic 1) 1.1 Introduction to the particulate nature of matter and chemical change - Essential Idea: Physical and Chemical properties depends on the ways in which different atoms combine 1.2 The mole concept − Essential Idea: The mole make it possible to correlate the number of particles with the mass that can be measured. 1.3 Reacting masses and volumes − Essential Idea: Mole ratios in chemical equations can be used to calculate reacting ratios by mass and gas volume. (IB D P syllabus Topic 9) 9.1 Introduction to Oxidation and Reduction − Essential Idea: Redox reactions play a key role in many chemical and biochemical processes. TOPIC 1 STOICHIOMETRIC RELATIONSHIP S TEACHER COPY – WITH SUGGESTED SOLUTIONS

IBDP Chemistry HL/Stoichiometric Relationships Page 2 1.1 Introduction to the particulate nature of matter and chemical change Essential idea: Physical and chemical properties depend on the ways in which different atoms combine.  Nature of Science: • Making quantitative measurements with replicates to ensure reliability —definite and multiple proportions. Understandings: • Atoms of different elements combine in fixed ratios to form compounds, which have different properties from their component elements. • Mixtures contain more than one element and/or compound that are not chemically bonded together and so retain their individual properties. • Mixtures are either homogeneous or heterogeneous. Applications and skills: • Deduction of chemical equations when reactants and products are specified. • Application of the state symbols (s), (l), (g) and (aq) in equations. • Explanation of observable changes in physical properties and temperature during changes of state. Guidance: • Balancing of equations should include a variety of types of reactions. • Names of the changes of state— melting, freezing, vaporization (evaporation and boiling), condensation, sublimation and deposition—should be covered. • The term “latent heat” is not required. • Names and symbols of elements are in the data booklet in section 5. 1.2 The mole concept Essential idea: The mole makes it possible to correlate the number of particles with the mass that can be measured.  Nature of Science: • Concepts— the concept of the mole developed from the related concept of “equivalent mass” in the early 19th century. Understandings: • The mole is a fixed number of particles and refers to the amount, n, of substance. • Masses of atoms are compared on a scale relative to 12C and are expressed as relative atomic mass (Ar) and relative formula/molecular mass (Mr). • Molar mass (M) has the uni