KNOWLEDGE AREA MATTER AND MATERIALS

Unit INDEX Bladsy KNOWLEDGE AREA MATTER AND MATERIALS 15 Unit 1 MACROSCOPIC PROPERTIES OF MATTER 15 Unit 2 Unit 3 Activity 1 17 Case study: Mopani worms 18 1.1 Mixtures 18 Practical activity 1 20 1.2 Pure substances 21 Activity 2 22 Practical activity 2 23 1.3 Names and formulae of substances 23 Activity 3 28 Exercise 1 29 1.4 Properties of materials 30 Practical activity 3 31 Activity 4 32 1.4.1 Electrical conductors and insulators 33 Experiment 1 33 1.4.2 Thermal conductors and insulators 35 Experiment 2 35 1.4.3 Magnetic and non-magnetic materials 36 Experiment 3 36 Exercise 2 38 Summary of Unit1 40 STATES OF MATTER AND THE KINETIC MOLECULAR THEORY 41 2.1 States of matter 41 Practical activity 4 41 2.1.1 Various states (phases) 43 Practical activity 5 47 2.1.2 Determining the state of a substance by looking at melting and boiling points 47 Exercise 3 48 Experiment 4 49 2.2 Kinetic molecular theory 50 Exercise 4 51 Summary of Unit 2 55 THE ATOM: THE BASIC BUILDING BLOCK OF ALL MATTER 59 3.1 Atomic models 59 Activity 5 60 3.2 Atomic structure 61 Activity 6 63 3.3 Isotopes 64 Exercise 5 65 3.4 Electron configuration 66 Exercise 6 69 Summary of Unit 3 73

Unit 4 THE PERIODIC TABLE 75 4.1 Composition 75 4.2 Information 76 4.2.1 General information 76 4.2.2 Zigzag line 77 4.2.3 Valence electrons 77 4.2.4 Reactivity 78 4.2.5 Atomic mass and atomic number 78 4.2.6 Trends in the Periodic Table (periodicity) 79 Activity 7 81 4.2.7 Atomic radius 81 4.2.8 Ionisation energy 82 4.2.9 Electron affinity 83 4.2.10 Electronegativity 84 Activity 8 85 Exercise 7 86 Summary of Unit 4 89 Unit 5 CHEMICAL BONDS 93 5.1 Covalent bonds 94 Exercise 8 95 5.2 Ionic bonds 96 5.3 Metallic bonds 96 Practical activity 6 97 Exercise 9 98 Mind maps of Unit 5 99 KNOWLEDGE AREA WAVES, SOUND AND LIGHT 101 Unit 1 TRANSVERSE PULSES 101 1.1 Pulses 101 Practical activity 7 103 Exercise 10 104 1.2 Interference 104 Practical activity 8 106 Exercise 11 107 Summary of Unit 1 108 Unit 2 TRANSVERSE WAVES 109 2.1 Transverse waves 109 2.2 Interference 111 2.3 Wave speed 113 Exercise 12 114 Summary of Unit 2 117 Unit 3 LONGITUDINAL WAVES 119 3.1 Longitudinal waves in a spring 119 Practical demonstration 1 119 3.2 Representation of longitudinal waves 121 Exercise 13 124 Summary of Unit 3 125 Unit 4 SOUND 127 Practical activity 9 127 Practical activity 10 127 Exercise 14 130 4.1 Reflection 130

4.2 Pitch 131 Practical activity 11 131 4.3 Loudness 132 4.4 Quality 133 Practical activity 12 133 Exercise 15 135 4.5 Ultrasound 137 Exercise 16 138 Summary of Unit 4 139 Unit 5 ELECTROMAGNETIC WAVES 141 5.1 Wave/particle properties of EM radiation 141 5.2 The nature of EM waves 141 5.3 The electromagnetic spectrum 142 5.4 Properties of electromagnetic waves 143 5.5 Penetrating ability 143 5.6 Disadvantages of EM radiation 144 5.7 Particle nature of EM waves 145 5.8 Inherent sense of danger 146 Exercise 17 147 Summary of Unit 5 148 Question paper 151 KNOWLEDGE AREA MATTER AND MATERIALS 157 Unit 6 MATTER IS COMPOSED OF PARTICLES 157 Experiment 5 158 Practical activity 13 159 6.1 Chemical bonds 159 6.1.1 Covalent bonds 159 6.1.1.1 Covalent molecular structures 159 Case study: The buckyball or buckminsterfullerene 160 6.1.1.2 Covalent network structures (macromolecules) 161 6.1.2 Ionic bonds 162 6.1.3 Metallic bonds 162 6.2 Different types of formulae 162 6.2.1 Molecular formulae 162 6.2.2 Empirical formulae 162 Practical activity 14 162 6.3 Models of molecules 163 Activity 9 164 Exercise 18 166 Summary of Unit 6 168 Question paper 169 KNOWLEDGE AREA CHEMICAL CHANGE 175 PHYSICAL AND CHEMICAL CHANGE 175 1.1 Separation of particles 175 1.1.1 Physical change 175 1.1.1.1 Change of condition (state) 176 Practical activity 15 178 1.1.1.2 Change of shape 179 1.1.1.3 Colour change 179 Exercise 19 180 1.1.2 Chemical change 181

Practical activity 16 182 1.1.3 Change in particles and mass 183 Experiment 6 183 Experiment 7 (demonstration) 184 Exercise 20 185 1.2 Laws 186 1.2.1 Law of constant composition 186 Practical activity 17 186 1.2.2 Law of conservation of mass 187 1.2.3 Law of volume relationships in gas reactions 188 Practical activity 18 188 Experiment 8 189 Experiment 9 189 Exercise 21 190 Summary of Unit 1 191 Unit 2 WRITING AND BALANCING CHEMICAL EQUATIONS 193 2.1 Balancing of chemical reactions 193 Exercise 22 196 2.2 Energy changes 197 Exercise 23 198 Summary of Unit 2 198 KNOWLEDGE AREA ELECTRICITY AND MAGNETISM 199 Unit 1 MAGNETISM 199 1.1 Magnetic poles 200 1.2 Magnets exert forces on each other 200 1.3 Magnetic and non-magnetic materials 200 1.4 Magnetic fields 201 1.4.1 Direction of a magnetic field 202 Practical activity 19 202 1.4.2 Magnetic field around a bar magnet 203 1.5 Theory of magnetism 204 1.6 Electromagnets and permanent magnets 205 1.7 The earth s magnetic field 205 1.7.1 Importance of the earth s magnetic field 206 1.7.2 Solar winds 206 1.7.3 Polar auroras 206 1.7.4 Magnetic (geomagnetic) storms 207 1.7.5 Migration of animals 207 Exercise 24 207 Summary of Unit 1 209 Unit 2 ELECTROSTATICS 211 2.1 Charges 211 Practical activity 20 212 2.2 Distribution of charge 213 2.2.1 Friction 213 2.2.2 Contact 214 2.2.3 Induction 215 Practical activity 21 216 2.3 Conservation of charge 217 2.4 Conductors and insulators 218

Exercise 25 218 Summary of Unit 2 222 Unit 3 ELECTRICAL CIRCUITS 223 3.1 Circuits 223 Activity 10 225 3.2 Potential difference 226 Practical demonstration 2 229 Exercise 26 230 3.3 Current strength 231 Experiment 10 233 Experiment 11 234 Exercise 27 235 3.4 Resistance 235 3.5 Ohm s law 237 Exercise 28 240 Summary of Unit 3 244 Question paper 246 KNOWLEDGE AREA CHEMICAL CHANGE 251 Unit 3 REACTIONS IN AQUEOUS SOLUTIONS 251 3.1 Ions in aqueous solutions 251 3.1.1 Dissociation and ionisation 252 3.1.2 Hydration 253 3.1.3 Chemical equation for the dissolution process 253 Practical activity 22 255 Case study: Hard and soft water 256 Case study: Acid rain 257 Exercise 29 257 3.2 Electrolysis and the extent of ionisation as a measure of conductivity 258 Experiment 12 259 Exercise 30 260 3.3 Precipitation reactions 262 3.3.1 What is a precipitation reaction? 262 3.3.2 Method of writing equations for the precipitate reactions 262 3.3.3 Tests for anions 263 Experiment 13 264 Exercise 31 265 3.4 Other chemical reactions in aqueous solutions 267 3.4.1 Ion exchange reactions 267 A. Precipitation reactions 267 B. Gas formation 267 C. Acid base reactions (transfer of protons) 268 3.4.2 Redox reactions 270 Experiment 14 271 Exercise 32 272 Summary of Unit 3 275 Unit 4 QUANTITATIVE ASPECTS OF CHEMICAL CHANGE 279 4.1 Mol concept 279 4.1.1 Atomic mass 282 4.1.2 Molar mass and formula mass 282

Exercise 33 284 4.2.1 Relationship between mol, mass and molar mass 284 4.2.2 Empirical formula 286 Exercise 34 287 4.3 Determining the composition of compounds 288 4.3.1 Determine the mol amount of water of crystallisation in copper(ii) sulphate 288 4.3.2 Percentage composition of a compound 288 Exercise 35 289 4.4 Molar gas volume and concentration 289 4.4.1 Molar gas volume 289 Exercise 36 290 4.4.2 Concentration 291 Exercise 37 292 4.5 Stoichiometric calculations 293 4.5.1 Calculations based on balanced equations 293 Exercise 38 295 Summary of Unit 4 298 Question paper 300 KNOWLEDGE AREA MECHANICS 303 Unit 1 SCALARS AND VECTORS 303 1.1 Introduction 303 1.1.1 Physical units 303 1.1.2 Direction of a vector 305 1.1.3 Graphical representation 306 1.1.4 Representation of a vector 307 1.1.5 Net or resultant vector 307 1.1.6 Addition of vectors 307 Exercise 39 309 Summary of Unit 1 310 Unit 2 MOVEMENT IN ONE DIMENSION 311 2.1 Position 311 2.2 Movement in one dimension 313 2.3 Distance and displacement 314 Practical activity 23 317 Exercise 40 318 2.4 Speed 319 2.5 Velocity 320 Exercise 41 324 2.6 Acceleration 325 Experiment 15 336 Exercise 42 337 Summary of Unit 2 339 Unit 3 DESCRIBING MOVEMENT 343 3.1 Instantaneous speed and instantaneous velocity 343 3.2 Graphs of motion 344 3.2.1 Constant velocity 345 Activity 11 347 3.2.2 Constant positive acceleration 348 Activity 12 352 3.2.3 Constant negative acceleration 352 Activity 13 354

Activity 14 355 3.2.4 Distance-time and speed-time graphs 358 3.2.5 Application of graphs 358 Activity 15 363 Exercise 43 365 3.3 Equations of motion 371 Exercise 44 378 Summary of Unit 3 380 Unit 4 ENERGY 383 4.1 Gravitational potential energy 383 4.2 Kinetic energy 385 Exercise 45 386 4.3 Mechanical energy and the law of conservation of mechanical energy 386 Practical activity 24 387 Exercise 46 394 Summary of Unit 4 396 Question paper 397 KNOWLEDGE AREA CHEMICAL SYSTEMS 403 HYDROSPHERE 403 1. Why is water important? 404 2. Necessity of the watercycle 404 3. Processes in a hydrosphere 406 4. The distribution of water 407 Exercise 47 408 5. Systems on earth 409 6. How does sunlight affect the water cycle? 411 7 The hydrosphere s interaction with 412 7.1 Atmosphere 412 7.2 Biosphere 413 7.3 Lithosphere 414 8. Influence of dams on the environment 414 Activity 16 416 Project: Quality and purity of water 416 Exercise 48 417 Summary of Knowledge Area 419 Question paper 421 Information sheets 424 Work cited 427