Topic 2 Bonding Structure and the Properties of Matter

• What do chemists use theories of structure and bonding for?

  To explain physical and chemical properties
• What types of structures can atoms be arranged in?

  Molecular and giant structures
• How do theories of bonding help scientists?

  They engineer new materials with desirable properties
• What are the three types of strong chemical bonds?

  Ionic, covalent, and metallic
• What particles are involved in ionic bonding?

  Oppositely charged ions
• What is the nature of covalent bonding?

  Atoms share pairs of electrons
• What characterizes metallic bonding?

  Atoms share delocalised electrons
• In which compounds does ionic bonding occur?

  Compounds formed from metals and non-metals
• Where does covalent bonding occur?

  In most non-metallic elements and compounds
• Where does metallic bonding occur?

  In metallic elements and alloys
• What happens to metal atoms when they react with non-metal atoms?

  Electrons are transferred from metal to non-metal
• What do metal atoms become after losing electrons?

  Positively charged ions
• What do non-metal atoms become after gaining electrons?

  Negatively charged ions
• What electronic structure do ions produced by metals and non-metals have?

  The electronic structure of a noble gas
• How can the electron transfer in ionic compounds be represented?

  By a dot and cross diagram
• What should students be able to do with dot and cross diagrams?

  Draw them for ionic compounds from specified groups
• How does the charge on ions relate to the periodic table?

  It relates to the group number of the element
• What is an ionic compound?

  A giant structure of ions
• What holds ionic compounds together?

  Strong electrostatic forces of attraction
• What is the structure of sodium chloride?

  A giant ionic lattice
• What should students be able to deduce from a diagram of an ionic compound?

  If the compound is ionic
• What are the limitations of using different diagrams for ionic structures?

  They may not accurately represent the structure
• How can students work out the empirical formula of an ionic compound?

  From a given model or diagram
• What happens when atoms share pairs of electrons?

  They form covalent bonds
• What can covalently bonded substances consist of?

  Small molecules or giant structures
• What should students be able to draw for common small molecules?

  Dot and cross diagrams
• How can covalent bonds be represented in diagrams?

  Using a line to represent a single bond
• What are the limitations of using diagrams to represent molecules?

  They may not show all interactions accurately
• What characterizes the structure of metals?

  Giant structures of atoms in a regular pattern
• What happens to the electrons in metal atoms?

  They are delocalised and free to move
• What gives rise to strong metallic bonds?

  The sharing of delocalised electrons
• What are the three states of matter?

  Solid, liquid, and gas
• What occurs at the melting point?

  Melting and freezing take place
• What occurs at the boiling point?

  Boiling and condensing take place
• How can the three states of matter be represented?

  By a simple model with solid spheres
• What does particle theory explain?

  Melting, boiling, freezing, and condensing
• What affects the amount of energy needed to change state?

  The strength of forces between particles
• How do the forces between particles relate to melting and boiling points?

  Stronger forces lead to higher melting and boiling points
• What are the limitations of the simple model of matter?

  It lacks forces and represents particles as solid spheres
• What should students be able to predict regarding states of substances?

  Their states at different temperatures