Montfort Sec 6092 Compiled Notes 2025

1 MONTFORT SECONDARY SCHOOL CHEMISTRY 6092 REVISION NOTES 2024 Name: _____________________________________ Class: ______________ CONTENT PAGE No Subject Content Page 1.1 Experimental Design (Chapter 1) 2 1.2 Methods of Purification and Analysis (Chapter 1) 3 2.1 Kinetic Particle Theory (Chapter 2) 6 2.2 Atomic Structure (Chapter 3) 9 3.1 – 3.3 Chemical Bonding (Chapter 4) 11 3.4 Structure and Properties of Materials (Chapter 5) 17 4.1 Formulae and Equation Writing (Chapter 6) 20 4.2 The Mole Concept and Stoichiometry (Chapter 7) 24 5.1 Acids and Bases (Chapter 8) 28 5.2 Salts (Chapter 9) 30 5.3 Ammonia (Chapter 10) 35 6 Qualitative Analysis (Chapter 11) 36 7.1 Oxidation and Reduction (Chapter 12) 38 7.2 Electrochemistry (Chapter 13) 43 8.1 – 8.3 The Periodic Table (Chapter 14) 47 8.4 Reactivity Series (Chapter 15) 49 9 Chemical Energetics (Chapter 16) 53 10 Rate of Reactions (Chapter 17) 55 11.1 Fuels and Crude Oils (Chapter 18) 61 11.2 Hydrocarbons (Chapter 19) 64 11.3 Alcohols, Carboxylic Acids and Esters (Chapter 20) 70 11.4 Polymers (Chapter 21) 73 12 Maintaining Air Quality (Chapter 22) 76

2 1.1 Experimental Design Key Concept I Key Concept II 1. Collection of Gases downward delivery of gas upward delivery of gas displacement of water For • gas denser than air (high density / heavier) For • gas less dense than air (low density / lighter) For • for gases that are insoluble / slightly soluble in water Examples: Chlorine Hydrogen chloride Examples: Ammonia Examples: Hydrogen Oxygen Carbon dioxide 2. Collection of Gases AND Measuring the Volume of Gas Quantity S.I. Unit Apparatus for measurement time second (s) [1h = 60 min] [1 min = 60 s] Electronic stopwatch temperature Kelvin (K) more commonly used - degree Celsius (°C) Laboratory thermometer mass Kilogram (kg) Other units – gram (g) [1 kg = 1000 g] Electronic balance volume Cubic metre (m3) Other units - litre (l), cubic centimetre (cm3) [1 m3 = 1000dm3] [1 dm3 = 1000cm3] liquid Pipette – fixed volumes (eg. 20.0 cm3, 25.0 cm3) Burette – accuracy to 2 d.p. (eg. 24.85 cm3) Measuring cylinder – accuracy to 1 d.p (eg. 20.5 cm3) gas gas syringe

3 1.2 Methods of Purification and analysis Key Concept I Types of Separation Techniques Separation technique Commonly asked questions Filtration 1. Essay type question, where you are given an insoluble solid. 2. You will be expected to draw a labelled diagram. ** Residue : insoluble solid ** Filtrate: liquid Evaporation / Crystallisation 1. Essay type question, where you are required to obtain dry solid from a solid-liquid mixture. 2. You will be expected to draw a labelled diagram. 3. For evaporation, heat to dryness 4. For crystallisation, heat to saturation point / crystallisation point. ** Evaporation cannot be used for substances that decompose on heating.

4 Distillation (solid-liquid mixture, e.g. distillation of seawater) 1. At which position (A or B) would the temperature be 100oC? (Ans: B. A contains impurities, hence the boiling point is not at 100 oC) 2. What is the purpose of the condenser? (Ans: to cool and condense vapours. REJECTED ANS: To condense the vapour) 3. Draw arrows to indicate where water enters and exit the condenser. (BITO: Bottom In Top Out) 4. What is the purpose of boiling chips? (Ans: To ensure smooth boiling) 5. Identify the distillate in this distillation experiment (Ans: water) Fractional distillation (liquid-liquid mixture) 1. What is the purpose of fractional distillation? (Ans: to separate liquids with close boiling points) 2. What are some industrial application of fractional distillation? (Ans: Refining crude oil, separating air into its components) ** liquid with lower boiling point will distil first. thermometer A B condenser distillate boiling chips water in water out Fractionating column condenser water in water out

5 Chromatography 1. Which substance has the highest solubility? (Ans: sugar 4) 2. Which substance has the lowest solubility? (Ans: sugar 3) 3. Which substances does the mixture contain? (Ans: sugars 2 and 4) 4. Why is the starting line drawn in pencil? (Ans: Pencil lead is not soluble in most solvents) 5. Name a suitable solvent. (Ans: water, ethanol) ** More soluble in solvent → travel faster and further up the chromatogram. Key Concept II Purity Check Pure substance Mixture Composition Fixed Not fixed Boiling point & melting point Fixed Varied/ Over a range of temperature Chromatogram One spot More than one spot Example: How does one find out of the substance is pure? Determine the melting and boiling point of the substance. If it melts and boils at a fixed temperature, it is a pure substance.

6 2.1 Kinetic Particle Theory Key Concept I 1. Physical state at room temperature (25oC) depends on the boiling and melting points. Key Concept II Properties of the 3 states of matter Property Solid Liquid Gas Shape Fixed Not fixed Not fixed Volume Fixed Fixed Not fixed Compressibility Cannot be compressed Cannot be compressed Can be compressed Key Concept III Change in states melting point boiling point Solid Liquid Gas SOLID LIQUID GAS melting freezing condensation evaporation/ boiling sublimation

7 Key Concept IV Kinetic Particle Theory*** Solid Liquid Gas 2-D representation of the arrangement of particles Arrangement of particles • Closely packed • Regular/orderly • Closely packed • Disorderly/ irregular • Far apart • irregular Attractive forces between particles • Very strong • Strong • Weak Kinetic energy of particles • Very low • High • Very high Particle motion • Vibrate about a fixed position • Slide over each another • Rapidly in any direction ** For changes from one state to another: emphasise on the changes in spacing/ movement (e.g. closer/ faster/ further) Example: What happens when a liquid boils? (Key focus: KPT, Energy changes) Particles gain enough energy to overcome the force of attraction (between them). The particles move further apart from each other and move with greater speed. Key Concept V Heating curve Temperature / oC Time/ min Solid Solid-liquid Liquid Liquid-gas Gas B.P. M.P. Energy used to allow particles to move faster Energy used to allow particles to move faster Energy used to allow particles to move faster Energy used to overcome forces between particles Energy used to overcome forces between particles

8 Key Concept VI Differences between boiling and evaporation Boiling Evaporation Occurs at the boiling point Occurs at any temperature Occurs throughout the liquid Occurs at the surface of the liquid Very fast Very slow Key Concept V Diffusion Diffusion is the net movement of particles from a region of higher concentration to a region of lower concentration until an equilibrium is achieved. The rate of diffusion is affected by: - Relative molecular mass (Mr) of the particles (higher Mr → slower rate of diffusion) - Temperature of substance (higher temperature → faster rate of diffusion)

9 2.2 Atomic Structure Key Concept I 1. Atoms are made up of