Unit 1

• Where do you find protons?

  inside the nucleus
• Where do you find electrons?

  Outside the nucleus
• Where do you find neutrons?

  inside the nucleus
• What are isotopes?

  atoms with the same no. of protons but different No. of neutrons.
• When can a covalent bond form?

  Only between non-metal atoms.
• Definition of ‘covalent bonding’
• What is the definition of a ‘covalent bond’?

  A covalent bond forms when 2 positive nuclei are held together by their common attraction for a shared pair of electrons
• What are the diatomic molecules?

  B2, O2, F2, I2, N2, C2, H2
• what kind of bonds and attractions do ‘covalent molecular’ substances have?

  Covalent Molecular Substances have strong covalent bonds within the molecules and only weak attractions between the molecules.
• what can covalent substances be formed as?

  Covalent Molecular substances OR Covalent Network structures
• What kind of melting and boiling points do covalent molecular substances have?

  low melting and boiling points: only weak forces of attraction between the molecule is broken
• Do ‘covalent molecular’ substances conduct electricity?

  Nope, they don’t have charged particles which ar free to move
• What kind of bonds do ’covalent network‘ structures have?

  Covalent Network structures have a network of strong covalent bonds within one giant structure
• What kind of boiling points and melting points do covalent network structures have?

  Covalent network structures have very high melting and boiling points because the network of strong covalent bonds don’t easily break
• Can covalent network structures dissolve?

  Covalent network structures do not dissolve.
• Do covalent network structures conduct electricity?

  Nope, because they don’t have charged particles which are free to move.
• When are ions formed?

  Ions are formed when atoms lose or gain electrons to obtain the stable electron

  arrangement of a noble gas.
• Metal atoms (gain/lose) electrons forming positive ions?

  Lose
• Non-metal atoms (gain/lose) electrons forming negative ions?

  gain
• What kind of attractions does ionic bonds have?

  Ionic bonds are the electrostatic attraction between positive and negative ions.
• What do ionic compounds form?

  Ionic Lattice structures.
• What kind of boiling points and melting points do ionic compounds have?

  Ionic compounds have high melting and boiling points because strong ionic bonds must be

  broken in order to break up the lattice.
• Are ionic compounds soluble in water?

  Yes
• Do Ionic compounds conduct electricity?

  Ionic compounds conduct electricity only when molten or in solution as the lattice structure

  breaks up allowing the ions to be free to move.
• How many elements are in a compound ending with ‘-ide’?

  Two.
• How many elements are in a compound ending with ‘-ite’?

  three, indicating that oxygen in present.
• How many elements are in a compound ending with ‘-ate’?

  Three, indicating that oxygen is present.
• When is a solution formed?

  A solution is formed when a solute is dissolved in a solvent.
• How is water neutral?

  H2O(l) <=> H+ (aq) OH- (aq)
• Why is a solution more acidic?

  Acidic solutions have a higher concentration of H+(aq) ions than OHˉ(aq) and have a pH

  below 7.
• Why Is a solution more alkaline?

  Alkaline solutions have a higher concentration of OHˉ(aq) ions than H+(aq) ions and have

  a pH above 7.
• What will happen if you dilute an acidic solution?

  Dilution of an acidic solution with water will decrease the concentration of H+(aq) and the

  pH will increase towards 7.
• What will happen if you dilute an alkaline solution?

  Dilution of an alkaline solution with water will decrease the concentration of OHˉ(aq) and

  the pH will decrease towards 7.
• What kind of oxides form acidic solutions when dissolved in water?

  Soluble non-metal oxides dissolve in water forming acidic solutions.
• What kinds of oxides form alkaline solutions when dissolved in water?


  Soluble metal oxides dissolve in water to form alkaline solutions: metal oxide + water —> metal hydroxide
• What are bases?

  bases that dissolve in water form alkaline solutions.
• What are the bases?

  Metal oxides, metal hydroxides, metal carbonates and ammonia neutralise acids
• What is a neutralisation reaction?

  A neutralisation reaction is one in which a base reacts with an acid to form water. A salt is

  also formed in this reaction.
• What are the equations of neutralising reactions?

  a metal oxide + an acid —> a salt + water

  a metal hydroxide + an acid —> a salt + water

  a metal carbonate + an acid —> a salt + water + carbon dioxide
• What are spectator ions?

  Spectator ions are ions that remain unchanged by the reaction.