Stage 1. Chemistry. Written by. Mr Ian Kershaw. BSc Dip Ed

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1 Stage 1 Written by Chemistry Mr Ian Kershaw BSc Dip Ed

2 The Author Ian Kershaw B.Sc., Dip.Ed. Ian has taught senior Chemistry since He was a member of the SSABSA Subject Advisory Committee for some years in the 1990s. Ian has extensive experience, over 13 years, as a marker of SACE Stage 2 examinations. He has taught in both metropolitan and country high schools and taught for 11 years in distance education. Ian is the author of the Stage 2 Chemistry Fundamentals Revision Guide that has been developed over the past decade. Publishing Information This booklet is part 2 of a series of six Stage 1 booklets designed for the SACE Stage 1 Chemistry course commencing in 2017 in South Australia. This booklet is designed to complement other resources students may have in this particular subject. This Unit is published by Total Chemistry ABN ISBN This booklet and others in the Stage 1 series were first published in Copyright Total Chemistry Ian Kershaw totalchemistry@bigpond.com Copyright information Unless permitted under the Copyright Act of 1968 (& subsequent amendments), no part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means without prior permission of the copyright owner. The author has made every attempt to trace and acknowledge copyright. The author apologises for any accidental infringement and would be quite happy to reach an amicable arrangement in any such case.

3 SACE STAGE 1 CHEMISTRY Unit 1. Materials and their Atoms 1.1. Properties and uses of materials 1.2. Atomic structure 1.3. Quantities of atoms 1.4. The Periodic Table Unit 2. Combining Atoms 2.1. Types of materials 2.2. Bonding between atoms 2.3. Quantities Unit 3. Molecules 3.1. Molecular polarity 3.2. Interactions between molecules 3.3. Hydrocarbons 3.4. Polymers Unit 4. Mixtures and Solutions 4.1. Miscibility and solutions 4.2. Solutions of ionic substances 4.3. Quantities in reactions 4.4. Energy in reactions Unit 5. Acids and Bases 5.1. Acid-base concepts 5.2. Reactions of acids and bases 5.3. The ph scale Unit 6. Redox Reactions 6.1. Metal reactivity 6.2. Concepts of oxidation and reduction 6.3. Electrochemistry

4 Unit 2 Combining Atoms Page 2.1 Types of Materials 3 Classification of Substances 3 Structures of Substances 4 Metallic Properties 5 Ionic Properties 6 Covalent Network Properties 7 Covalent Molecular Properties 7 Use of Melting Points 8 Use of electrical Conductivity Bonding Between Atoms 9 Bonding Between Metals 11 Alloys 11 Bonding Between Metals and Non-Metals 11 Ionic formula 14 Electron Configuration of Atoms and Ions 15 Bonding Between Non-Metal Atoms 16 Polar Bonds and Molecules 17 Electronegativity 18 Structural & Molecular Formula 18 Continuous Covalent Substances 19 Allotropes of Carbon 19 Fullerenes Quantities of Molecules & Ions 22 Percentage Composition By Mass 22 Molar expressions 24 Empirical Formula 24 Stoichiometry (Mass to Mass) 24 Answers to Questions in Notes 26 Questions 28 Solutions to Questions 51 Notes 74 Periodic Table 77

5 Unit 2. Combining Atoms 2.1. Types of materials Materials can be classified according to their structure and bonding into four types of substances. Melting points can be used to classify materials into molecular and non-molecular lattices. Electrical conductivity of non-molecular materials provides evidence for three types of primary bonding: metallic, ionic, and covalent. Classify materials as molecular, metallic, ionic, and covalent network, given relevant conductivity and melting point data. CLASSIFICATION OF SUBSTANCES SUBSTANCES TEST 1: MELTING AND BOILING POINT HIGH melting point and boiling point LOW melting point and boiling point NON-VOLATILE STRONG FORCES * NETWORKS VOLATILE WEAK FORCES * MOLECULAR Compounds & elements of non-metals TEST 2: ELECTRICAL IVITY TEST 2: ELECTRICAL IVITY WHEN IN SOLID OR MOLTEN metals METALLIC NETWORK e.g. metals or alloys DO NOT WHEN SOLID BUT DO WHEN MOLTEN OR IN SOLUTION. compounds of metals and non-metals IONIC NETWORK e.g. NaCl or KOH etc. DO NOT IN SOLID OR MOLTEN STATES. compounds or elements of non-metals COVALENT NETWORK e.g. Carbon as diamond or graphite and silicon dioxide (sand) DO NOT IN SOLID OR MOLTEN STATES. COVALENT MOLECULAR There three types of primary bonds are metallic, covalent and ionic. Primary bonds have very strong forces of attraction between particles.

6 Name Metal network Ionic network The two possible types of structures are molecular and networks (lattices). A molecule is the smallest discrete individual particle of an element or a compound that displays the chemical properties of the substance. Molecules exist between most non-metal atoms. Attractive forces that exist between molecules are known as secondary interactions. Networks, also known as lattices, exist as regular 2D or 3D arrangements of atoms or ions where the forces between particles are very strong. Structure A regular 3D arrangement of metal ions in a sea of mobile electrons. The metallic bond involves forces of attraction between the positively charged ions and the mobile electrons. These forces exist in 3D. A regular 3D arrangement of positively charged metal ions and negatively charged non-metal ions. The chemical bonds involve strong forces of attraction between the oppositely charged ions in 3D. Covalent network Covalent molecular A regular 2D/3D arrangement of non-metal atoms. The bonds involve forces of attraction between the positively charged nuclei of the atoms and the negatively charged pair(s) of electrons shared between them. Graphite, diamond or silicon dioxide (sand) are examples of covalent networks. Almost all other substances comprising non-metal atoms are covalent molecular. These substances exist as discrete units of nonmetallic atoms, called molecules, that are chemically bonded together. Strong covalent bonding occurs between the atoms within the molecules. Weaker secondary forces of attraction exist between molecules (intermolecular forces/secondary interactions). These descriptions are all based on observations of physical properties from experiments. Strong forces of the primary bonds exist in the three types of network substances to cause a change in state where particles are separated from their neighbours, a large