AQA GCSE Chemistry Bonding, Structure and the Properties of Matter PDF

The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The Pi...

The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club XL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL KnowIT! PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The GCSE Chemistry PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The AQA Topic – Bonding, structure and PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The the properties of matter PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The © Copyright The PiXL Club Ltd, 2017 PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The This PiXL Club Theresource is strictly PiXL Club The forThe PiXL Club the use PiXL ofThe Club member schools PiXL Club The PiXLfor asThe Club long PiXLasClub they Theremain members PiXL Club of The The PiXL Club PiXL The PiXL Club. Club It may The PiXL Clubnot Thebe copied, PiXL Club Thesold PiXL nor Clubtransferred The PiXL Clubto The PiXL Club The PiXL a third CluborThe party PiXLby used Club The the PiXL Club school Themembership after PiXL Club The PiXL Club The ceases. PiXLsuch Until Club time The PiXL Club be it may Thefreely PiXL Club Thewithin used PiXL Club theThe PiXL Clubschool. member The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The All opinions and contributions are those of the authors. The contents of this resource are not connected with nor endorsed by any other company, PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The organisation PiXL Club The PiXL CluborTheinstitution. PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The www.pixl.org.uk The PiXL Club Ltd, Company number 07321607 PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The PiXL Club The  Overview Bonding Bonding, Structure and the properties of matter Chemical bonds Ionic bonding Ionic compounds Covalent bonding Metallic bonding Properties of substances States of matter State symbols Properties of ionic compounds Properties of small molecules Polymers Giant covalent structures Properties of metals and alloys Structure and bonding of carbon Diamond, graphite Graphene and fullerenes Nanoparticles (Chemistry ONLY) Size of particles Uses of nanoparticles LearnIT! KnowIT! Bonding part 1 Chemical bonds Ionic bonding Ionic compounds  Chemical bonds There are three types of strong chemical bonds: Ionic Covalent Metallic Ionic Covalent Metallic Particles are Particles are atoms Particles are atoms oppositely charged which share pairs of which share ions electrons delocalised electrons Most non‐metallic Between metals and elements In metallic elements non‐metals Between non‐metals and alloys and non‐metals You need to be able to explain chemical bonding in terms of electrostatic forces and the transfer of electrons.  Ionic bonding Ionic bonds form between metals and non‐metals. Ionic bonding involves the transfer of electrons in the outer shells. Metals lose electrons to become positively charged ions and non‐metals gain electrons to become negatively charged ions. The elements in Group 1 react with the elements in Group 7. Groups 1 elements can each lose one electron. This electron can be given to an atom from Group 7, they both achieve the stable electronic structure of a noble gas.  Ionic bonding The electrostatic attraction between the oppositely charged Na+ ions and Cl‐ ions is called ionic bonding. The electron transfer during the formation of an ionic compound can be represented by a dot and cross diagram: When completing diagrams always include: The correct number of electrons on outer shells The charge The charge on the ions produced by metals in group 1 and 2 and by non‐metals in group 6 and 7 relates to the group number of the element in the periodic table. For example group 1 form 1+ ions, group 3 form 3+ ions, group 6 form 2‐ ions and group 7 form 1‐ ions.  Ionic bonding Magnesium oxide: Calcium Chloride: Sometimes the atoms reacting need Each calcium atom (2, 8, 8, 2) needs to to gain or lose two electrons to gain a lose two electrons but each chlorine stable noble gas structure. Each atom (2, 8, 7) needs to gain only one magnesium loses two electrons and electron. each oxygen gains two electrons. This means that two chlorine atoms Magnesium ions have the formula react with every one calcium atom, Mg2+, while oxide ions have the giving the formula CaCl2 formula O2‐. This means that one magnesium atom reacts with one oxygen atom, giving the formula MgO  Ionic compounds An ionic compound is a giant structure of The structure of sodium chloride ions. can be represented in the following forms: Ionic compounds are held together by strong electrostatic forces of attraction between oppositely charges ions. These forces act in all directions in the lattice – this is called ionic bonding. Empirical formula The models can indicate the chemical formula of a compound by the simplest ratio of atoms or ions in models of their giant structure – this is called the empirical formula. ‐ The models never accurately e.g. there is a 1:1 ratio of sodium to reflect the many millions of chlorine in sodium chloride, so the formula atoms/ions bonded together in is NaCl. the giant lattices QuestionIT! Bonding part 1 Chemical bonds Ionic bonding Ionic compounds  Bonding PART 1 – QuestionIT 1. What are the three types of strong chemical bond? 2. What particles are found in: a) Ionic bonding b) Covalent bonding c) Metallic bonding? 3. Which type of bonds occurs when metals combine with non‐ metals? 4. What type of bonding occurs in carbon dioxide? Why? 5. What type of bonding occurs in alloys?  Bonding PART 1 – QuestionIT 6. What happens to the electrons in ionic bonding? 7. What electronic structure do the ions produced by metals in Groups 1 and 2 and the non‐metals in Groups 6 and 7 have? 8. What is the link between the charge number on the ions in groups 1, 2 and 3 and their group number ? 9. What is an ionic compound? 10. How are ionic compounds held together?  Bonding PART 1 – QuestionIT 11. Why is the ball and stick model not an accurate representation of the structure of an ionic compound? 12. Draw a diagram to show how potassium and chlorine atoms join together to form ions. 13. Explain how you can use the following model to work out the empirical formula of sodium chloride. AnswerIT! Bonding part 1 Chemical bonds Ionic bonding Ionic compounds  Bonding PART 1 – QuestionIT 1. What are the three types of strong chemical bond? Ionic, covalent, metallic. 2. What particles are found in: a) Ionic bonding oppositely charged ions. b) Covalent bonding atoms which share electrons. c) Metallic bonding? Atoms which share delocalised electrons. 3. Which type of bonds occurs when metals combine with non‐ metals? Ionic. 4. What type of bonding occurs in carbon dioxide? Why? Covalent; two non‐metals. 5. What type of bonding occurs in alloys? Metallic.  Bonding PART 1 – QuestionIT 6. What happens to the electrons in ionic bonding? Transferred. 7. What electronic structure do the ions produced by metals in Groups 1 and 2 and the non‐metals in Groups 6 and 7 have? Electronic structure of a noble gas. 8. What is the link between the charge number on the ions in groups 1, 2 and 3 and their group number ? Charge number is same as Group number. 9. What is an ionic compound? Giant structure of ions. 10. How are ionic compounds held together? Strong electrostatic forces of attraction; between oppositely charged ions.  Bonding PART 1 – QuestionIT 11. Why is the ball and stick model not an accurate representation of the structure of an ionic compound? Does not accurately depict the millions of ions in the lattice. The ions should touch each other/ there are no gaps between the ions. 12. Draw a diagram to show how potassium and chlorine atoms join together to form ions.  Ionic bonding PART 2 – QuestionIT 13. Explain how you can use the following model of sodium chloride to work out the empirical formula. Count the number of each type of atom in the giant structure and work out simplest whole number ratio. LearnIT! KnowIT! Bonding PART 2 Covalent bonding Metallic bonding  Covalent bonding - PART 1 When atoms share pairs of electrons, they form covalent bonds. These are STRONG bonds. Covalently bonded substances may be: Small molecules, very large molecules or giant covalent structures. H NH3 You can deduce the molecular H2O formula of a substance from a given model or diagram O showing the atoms and bonds N in the molecule by counting the H H H H number of atoms. Polymers are examples of very large covalent molecules, they can be represented in the form: where ‘n’ = a very large number! Examples of covalently bonded substances with giant covalent structures are diamond and silicon dioxide.  Covalent bonding - PART 1 Covalently bonded substances may consist of small molecules. The covalent bond in molecules can be represented in the following models. Like all models, each one is useful but has some limitations. Ammonia NH3 Dot and cross with outer shells 2D with bonds: ‐ It shows the H‐N‐H bond as circles: incorrectly at 90° 3D ball and stick model: + Show which atoms are bonded together Dot and cross with + Show which atom the outer shells electrons: + Attempts to show the correct electrons in the bonds come H‐N‐H bond angle is 107.8° from + Shows the impact of the lone ‐ All electrons are identical pair  Metallic bonding The atoms in metals are built up layer upon layer in a regular pattern. They are another example of a giant structure. The electrons in the outer shell of metal atoms are delocalised and are free to move throughout the structure. The sharing of delocalised electrons leads to strong metallic bonds. Metallic bonding can be represented in the following form: QuestionIT! Bonding PART 2 Covalent bonding Metallic bonding  Bonding – Part 2 – QuestionIT 1. How are strong covalent bonds formed? 2. What are the three types of structure that can be formed by covalent bonding? 3. What are polymers an example of? 4. What type of structure do the following covalently bonded substances have? a) Water H2O b) Silicon dioxide SO2 c) Diamond C d) Poly(ethene)  Bonding – Part 2 – QuestionIT 5. What are the limitations of using dot and cross diagrams to represent covalent bonds? 6. How are atoms arranged in a metal? 7. Why are metallic bonds so strong? 8. What is the formula of the following model?  Covalent bonding PART 1 – QuestionIT 9. Draw a dot and cross diagram for water. 10. Describe the arrangement of particles in a metal. 11. Why are the particles that make up a metal described as positively charged? 12. What are delocalised electrons? AnswerIT! Bonding PART 2 Covalent bonding Metallic bonding  Bonding – Part 2 – QuestionIT 1. How are strong covalent bonds formed? Atoms share pairs of electrons. 2. What are the three types of structure that can be formed by covalent bonding? Small molecules, very large molecules, giant covalent molecules. 3. What are polymers an example of? Very large molecules. 4. What type of structure do the following covalently bonded substances have? a) Water H2O Small covalent. b) Silicon dioxide SO2 Giant covalent. c) Diamond C Giant covalent. d) Poly(ethene) Very large molecule.  Bonding – Part 2 – QuestionIT 5. What are the limitations of using dot and cross diagrams to represent covalent bonds? It shows the electrons differently, when they are the same and it does not show the bond angles or shape of the molecule. 6. How are atoms arranged in a metal? Giant structures of atoms, arranged in a regular pattern, delocalised electrons. 7. Why are metallic bonds so strong? Sharing of delocalised electrons. 8. What is the formula of the following model? CO2  Bonding – part 2 – QuestionIT 9. Draw a dot and cross diagram for water. 10. Describe the arrangement of particles in a metal. Atoms arranged neatly in rows; sea of delocalised electrons. 11. Why are the particles that make up a metal described as positively charged? The metal atoms lose outer shell electrons and therefore there are more protons (+) than electrons (−). 12. What are delocalised electrons? They are free‐moving electrons within structure; not associated with a particular atom. LearnIT! KnowIT! Properties of substances Part 1 States of matter State symbols  States of matter and state symbols There are three states of matter – solid, liquid and gas. To explain the properties of the states, the particle theory is used. It is based on the fact that all matter is made up of tiny particles and describes the movement and distance between particles. Solid Liquid Gas Close together, regular Close together, random Far apart, random pattern, vibrate on the arrangement, move arrangement, move spot. around each other. quickly. In chemical equations, the three states are shown as (s), (l), (g) and (aq) for aqueous solutions.  Changes of state Melting and freezing take place at the melting point. Boiling and condensing take place at the boiling point. The amount of energy required to change the state depends on the strength of the forces between the Freezing Melting particles of the substance. The stronger the forces between the particles the higher the melting and boiling point of the substance. The type of bonding and the structure of the substance Condensing Boiling depend on the particles involved. HT ONLY ‐ There are limitations of the particle model of matter: There are no forces All particles are shown as spheres The spheres are solid  Changes of state The graph shows a heating curve of a solid, which shows the temperature of a substance plotted against the amount of energy it has absorbed: A substance must absorb heat energy so that it can melt or boil. The temperature of the substance does not change during melting, boiling or freezing, even though energy is still being transferred. QuestionIT! Properties of substances Part 1 States of matter State symbols  Properties of substances – Part 1 – QuestionIT 1. What are the three states of matter? 2. What is used to represent particles in the simple particle model? 3. What takes place at the melting point? 4. What takes place at the boiling point? 5. What factor affects the amount of energy needed to change state?  Properties of substances – Part 1– QuestionIT 6. In chemical equations what symbols are used to show the states of matter? 7. In what state of matter do particles have the most energy? 8. What would eventually happen to a gas if pressure is increased? 9. HT ONLY: Explain the limitations of the particle model.  Properties of substances – Part 1 QuestionIT 10. The following represents the heating of ice: a) What change in state happens at stage 2? b) What is happening at stage 4? AnswerIT! Properties of substances Part 1 States of matter State symbols  Properties of substances – Part 1– QuestionIT 1. What are the three states of matter? Solid, liquid, gas. 2. What is used to represent particles in the simple particle model? Small solid spheres. 3. What takes place at the melting point? Melting and freezing. 4. What takes place at the boiling point? Boiling and condensing. 5. What factor affects the amount of energy needed to change state? Forces between molecules.  Properties of substances – Part 1– QuestionIT 6. In chemical equations what symbols are used to show the states of matter? Solid = (s); liquid = (l); gas = (g); aqueous = (aq) 7. In what state of matter do particles have the most energy? Gas. 8. What would eventually happen to a gas if pressure is increased? Condense into a liquid. 9. HT ONLY: Explain the limitations of the particle model. No forces, particles are shown as spheres, spheres are solid.  Properties of substances – Part 1– QuestionIT 10. The following represents the heating of ice: a) What change in state happens at stage 2? Melting/ freezing b) What is happening at stage 4? Boiling/ condensing LearnIT! KnowIT! Properties of substances Part 2 Ionic compounds Small molecules Polymers Giant covalent structures Metals and alloys  Properties of ionic compounds Structure Ionic compounds have regular structures called giant ionic lattices. There is strong electrostatic forces of attraction in all directions between oppositely changed ions. Properties High melting and boiling points – large amounts of energy is needed to break the many strong bonds and overcome the electrostatic attraction. Conduct electricity when molten or dissolved in water – ions are free to move and can carry charge.  Properties of small molecules Structure They have weak forces between the molecules. These weak forces are overcome when they change state not the strong covalent bonds. Properties Low melting and boiling points – small amounts of energy is needed to break the intermolecular forces. Most are gases or liquids. Do not conduct electricity – Particles do not have an overall electric charge. Intermolecular forces increase with the size of the molecules. So larger molecules have higher melting and boiling points.  Polymers Some covalently bonded substances have very large molecules, such as polymers. Structure Polymers are made up from many small reactive molecules that bond to each other to form long chains. The atoms in the polymer molecules are linked to other atoms by strong covalent bonds. The intermolecular forces between polymer molecules are relatively strong. Properties Solid at room temperature – Strong intermolecular forces.  Giant covalent structures Structure All atoms within the structure are linked by strong covalent bonds. These bonds must be broken for a solid to melt or boil. Properties Very high melting and boiling points – very large amounts of energy is needed to break the covalent bonds. Do not conduct electricity – Particles do not have an overall electric charge.  Properties of metals and alloys The giant structure of atoms with A metal mixed with other elements is strong metallic bonding gives most called an alloy. Alloys are harder than metals a high melting and boiling pure metals. Alloys are made from two point. or more different metals. Metals are malleable (can be Pure metal Alloy hammered into shape) and ductile (can be drawn out into a wire) because the layers of atoms (or ions) in a giant metallic structure can slide over each other Delocalised electrons in metals enable The different sized atoms of the metals electricity and heat to pass through distort the layers in the structure, the metal easily. making it more difficult for them to slide over each other, and so make the alloys harder than pure metals. For example, gold is naturally soft but adding copper to make jewellery stronger and last longer. QuestionIT! Properties of substances Part 2 Ionic compounds Small molecules Polymers Giant covalent structures Metals and alloys  Properties of substances – Part 2 – QuestionIT 1. Describe the structure of ionic compounds. 2. Why do ionic compounds have high melting and boiling points? 3. Why can ionic compounds conduct electricity when melted or dissolved in water? 4. What state of matter are small molecules normally found in? 5. Why do small molecules have low melting and boiling points?  Properties of substances – Part 2 – QuestionIT 6. What happens to the melting and boiling points as small molecules get bigger? Why? 7. Why don’t small molecules conduct electricity? 8. What are polymers? 9. How are the atoms in a polymer linked together? 10. Why are polymers normally solid at room temperature? 11. Give an example of a giant covalent structure.  Properties of substances – Part 2 – QuestionIT 12. Why do giant covalent structures have very high melting and boiling points? 13. Why do most metals have high melting and boiling points? 14. How are atoms arranged in pure metals? 15. What is an alloy? 16. Why do we use alloys, rather than pure metals, for many uses?  Properties of substances – Part 2 – QuestionIT 17. Why are metals good conductors of electricity? 18. What is thermal energy? 19. Why are metals good conductors of thermal energy? AnswerIT! Properties of substances Part 2 Ionic compounds Small molecules Polymers Giant covalent structures Metals and alloys  Properties of substances – Part 2 – QuestionIT 1. Describe the structure of ionic compounds. Regular, giant ionic lattice. 2. Why do ionic compounds have high melting and boiling points? Strong electrostatic forces of attraction between ions. 3. Why can ionic compounds conduct electricity when melted or dissolved in water? Ions are free to move, carry the charge. 4. What state of matter are small molecules normally found in? Gas or liquid. 5. Why do small molecules have low melting and boiling points? Weak forces between molecules/ intermolecular forces.  Properties of substances – Part 2 – QuestionIT 6. What happens to the melting and boiling points as small molecules get bigger? Why? Increases, intermolecular forces get bigger. 7. Why don’t small molecules conduct electricity? Do not have an overall electric charge. 8. What are polymers? Very large molecules made of repeating units. 9. How are the atoms in a polymer linked together? Strong covalent bonds. 10. Why are polymers normally solid at room temperature? Intermolecular forces relatively strong. 11. Give an example of a giant covalent structure. Diamond, graphite, silicon dioxide.  Properties of substances – Part 2 – QuestionIT 12. Why do giant covalent structures have very high melting and boiling points? Strong covalent bonds must be broken. 13. Why do most metals have high melting and boiling points? Strong metallic bonding. 14. How are atoms arranged in pure metals? Layers. 15. What is an alloy? Mixture of two elements, one of which is a metal. 16. Why do we use alloys, rather than pure metals, for many uses? They are harder as the layers are distorted.  Properties of substances – Part 2 – QuestionIT 17. Why are metals good conductors of electricity? Electrical charge carried by delocalised electrons. 18. What is thermal energy? Heat energy. 19. Why are metals good conductors of thermal energy? Energy is transferred by delocalised electrons. LearnIT! KnowIT! Properties of substances Part 3 Diamond Graphite Graphene and fullerenes  Diamond Diamond: In diamond, each carbon atom forms four covalent bonds with other carbon atoms in a giant covalent structure. Diamond is very hard – it is the hardest natural substance, so it is often used to make jewellery and cutting tools. Diamond has a very high melting and boiling point – a lot of energy is needed to break the covalent bonds. Diamond cannot conduct electricity – there are no free electrons or ions to carry a charge.  Graphite Graphite: In graphite, carbon atom forms three covalent bonds with three other carbon atoms, forming layers of hexagonal rings which have no covalent bonds between the layers. Graphite is soft and slippery – layers can easily slide over each other because the weak forces of attraction between the layers are easily broken. This is why graphite is used as a lubricant. Graphite conducts electricity – the only non‐metal to do so. One electron from each carbon atom is delocalised.  Graphene Graphene: This is a single layer of graphite – a layer of inter‐locking hexagonal rings of carbon atoms one atom thick. It is an excellent conductor of thermal energy and electricity (even better than graphite), has a very low density and is incredibly strong. It has many uses in the electronics industry.  Fullerenes Fullerenes: Fullerenes are molecules of carbon with hollow shapes. The structure is based on hexagonal rings of carbon atoms, but may have 5 or 7 carbon rings. The first to be discovered was Buckminsterfullerene (C60) which is spherical (like a football). Carbon nanotubes are cylindrical fullerenes with very high length compared to their diameter. This makes them useful for nanotechnology, electronics and materials. QuestionIT! Properties of substances Part 3 Diamond Graphite Graphene and fullerenes  Properties of substances – Part 3 – QuestionIT 1. In a diamond, how many covalent bonds does each carbon make? 2. Diamond does not conduct electricity. Why? 3. Name 2 other properties of diamond. 4. In graphite, how many covalent bonds does each carbon make? 5. Describe the structure of graphite. 6. Why is graphite soft?  Properties of substances – Part 3 – QuestionIT 7. Why does graphite conduct electricity? 8. How is graphite similar to metals? 9. What is graphene? 10.What are fullerenes? 11.What was the first fullerene to be discovered? 12.What are carbon nanotubes? 13.What are carbon nanotubes useful for? AnswerIT! Properties of substances Part 3 Diamond Graphite Graphene and fullerenes  Properties of substances – Part 3 – QuestionIT 1. In a diamond, how many covalent bonds does each carbon make? 4 2. Diamond does not conduct electricity. Why? No delocalised electrons. 3. Name 2 other properties of diamond. Hard, very high melting point. 4. In graphite, how many covalent bonds does each carbon make? 3 5. Describe the structure of graphite. Layers of hexagonal rings. 6. Why is graphite soft? Layers can slide over each other, weak forces between layers, no covalent bonds between layers.  Properties of substances – Part 3 – QuestionIT 7. Why does graphite conduct electricity? Each carbon has one delocalised electron. 8. How is graphite similar to metals? It contains delocalised electrons. 9. What is graphene? Single layer of graphite, 1 atom thick. 10.What are fullerenes? Molecules of carbon atoms with hollow shapes. 11.What was the first fullerene to be discovered? Buckminsterfullerene. 12.What are carbon nanotubes? Cylindrical fullerenes. 13.What are carbon nanotubes useful for? Electronics, nanotechnology and materials. LearnIT! KnowIT! Nanoparticles (Chemistry ONLY) Sizes of particles and their properties Uses of nanoparticles  Covalent bonding - PART 3 CHEMISTRY ONLY Nanoscience is the study of small particles that are between 1 and 100 nanometres in size. Particles consisting The size of a of fewer than 100 atoms are often typical called nanoclusters. nanoparticle is … 1 nanometre (1 nm) = 1 x 10‐9 metres (0.000 000 001m or a billionth of a metre). … to a football as a Nanoparticles are smaller than fine football is … particles (PM2.5) which have diameters between 1 x 10‐7 metres and 2.5 x 10‐6. To comprehend how small this is, coarse …to the Earth particles, like dust, have diameters between 1 x 10‐5 and 2.5 x 10‐6.  Covalent bonding - PART 3 CHEMISTRY ONLY Nanoparticles show different properties to the same materials in bulk as they have a high surface area to volume ratio. The diagram shows this idea: As particle size gets smaller, the surface area to volume ratio gets larger. As the side of cube decreases by a factor of 10 the surface area to Surface area 3x3x6 2x2x6 1x1x6 volume ratio increases by a (height x width x number of sides) factor of 10. =54 =24 =6 Nanoparticles show different Volume 3x3x3 2x2x2 1x1x1 properties to the same materials (height x width x length) in bulk and have a high surface =27 =8 =1 area to volume ratio. It also Surface to volume ratio 54/27 24/8 6/1 means that smaller quantities are (surface area / volume) needed to be effective than the =2 =3 =6 materials with normal particle sizes.  Covalent bonding ‐ PART 3 CHEMISTRY ONLY Nanoparticles have many applications in medicine, in electronics, in cosmetics and sun creams, as deodorants, and as Health care Cosmetics catalysts. Clothing New developments in nanoscience are very exciting but will need more Electronics Catalysts research into possible issues that might Uses of arise from their increased use. nanoparticles There are some concerns that Food nanoparticles may be toxic to people. Paints They may be able to enter the brain from the bloodstream and cause harm. Biomedical Some people think more tests should Sports equipment Industrial take place before nanoparticles of a material are used on a wider scale. Learn three examples for your exam QuestionIT! Nanoparticles (Chemistry ONLY) Sizes of particles and their properties Uses of nanoparticles  Nanoparticles CHEMISTRY ONLY – QuestionIT 1. What does nanoscience refer to? 2. What are nanoparticles? 3. What are coarse particles? 4. Why do nanoparticles have different properties from those for the same materials in bulk? 5. Name 5 uses of nanoparticles. AnswerIT! Nanoparticles (Chemistry ONLY) Sizes of particles and their properties Uses of nanoparticles  Nanoparticles CHEMISTRY ONLY – QuestionIT 1. What does nanoscience refer to? Structures that are 1‐100nm in size, a few hundred atoms. 2. What are nanoparticles? Smaller than fine particles. 3. What are coarse particles? Diameters between 1 x 10‐5m and 2.5 x10‐6m 4. Why do nanoparticles have different properties from those for the same materials in bulk? They have a high surface area to volume ratio. Smaller quantities are needed to be effective. 5. Name 5 uses of nanoparticles. Medicine, electronics, cosmetics, sunscreens, deodorants, catalysts.