Mr King – Chemistry Paper 1 Revision Question and Answer Sheets

1. Things to do • Test yourself regularly • Ask somebody at home to test you • Make flashcards of the questions and answers • Use these on Quizlet – Search “King’s Chem Revision” • You’ll have a weekly quiz on these questions • Remember, you can also use Seneca to keep revising Mr King – Chemistry Paper 1 Revision Question and Answer Sheets

2. History of the Atom 400 BC First Idea Spheres Early Greece 1897 Plum Pudding JJ Thompson Chemistry Revision Sheets - Topic 1 – The Atom Gold foil experiment showed atoms have a dense, positively charged nucleus 1905 Nuclear Model Ernest Rutherford 1913 Niels Bohr Electrons in shells 1932 James Chadwick Neutrons exist Current Atomic Model

3. Terminology Compound of Element X and Element Y Mixture of Element X and Element Y Element Y Element X Chemistry Revision Sheets - Topic 2 – Elements, Compound and Mixtures Separating Mixtures Chromatography Distillation Separate mixtures of soluble substances (ink, food colourings) Separate mixtures of two or more substances with different boiling points. The mixture is heated until one substance evaporated and removed, then cooled to condense back to a liquid. Crystallisation Filtration Separates a mixture of a liquid and an insoluble solid Separating a mixture of a soluble solid and a liquid

4. Group GroupGroup 1 7 0 • Group 1 – Alkali Metals • One electron in outer shell. • As you go down the group, the reactivity of the elements increases. This is because… more shells = more shielding = easier to lose electrons Chemistry Revision Sheets - Topic 3 – Periodic Table, Groups and Trends • Group 7 – Halogens • Seven electron in outer shell. • Non-metals. • As you go down the group, the reactivity of the elements decreases. This is because… more shells = more shielding = harder to gain electrons • As you go down the group melting/boiling points increase. At room temp. F/Cl = Gas. Br = Liquid. I = Solid. • Group 0 – Noble Gases • Unreactive. Full outer shells of electrons. • As you go down the group, the boiling points of the noble gases increases.

5. Ionic Bonding – Dot Cross Diagram Example Oxygen will gain two electrons from calcium atom to become a negative oxide ion (O2-). Oxygen has been reduced. Calcium will transfer two electrons to an oxygen atom to become a positive calcium ion (Ca2+). Calcium has been oxidised. Chemistry Revision Sheets - Topic 4a – Ionic Bonding Giant Ionic Lattice

6. Simple Covalent Bonding – Dot Cross Diagram Examples Shared pair of electrons, single bond Two shared pairs of electrons, double bond Chemistry Revision Sheets - Topic 4b – Covalent Bonding Giant Covalent Structures Diamond Graphite

7. Metallic Bonding Negative delocalised electrons Chemistry Revision Sheets - Topic 5 – Metallic Bonding, Alloys and Polymers Positive metal ions Alloy Different sized atoms. No layers. No Sliding. Harder. Monomer Polymer

8. Relative Formula Mass (Mr) Mr of CaCO3? 40 + 12 + (16x3) = 100 Moles If you have 20g of CaCO3, how many moles is this? Moles = Mass / Mr 20 / 100 = 0.2 moles Chemistry Revision Sheets – Topic 6 – Quantitative Chemistry Reacting Masses 0.5g of lithium reacts with oxygen. How much lithium oxide is made? 2Li + O2 Li2O Step 1) moles of lithium = mass / Mr = 0.5 / 7 = 0.071 moles Step 2) mole ratio Li : Li2O 2 : 1 0.071 : 0.0355 moles of lithium oxide Step 3) mass of lithium oxide = moles X Mr = 0.0355 x (7+7+16) = 1.065g Li2O From equation Concentration • What is the concentration if 1.5g of potassium iodide dissolves in 150cm3 of solution? • Step 1) Convert units. 150cm3 = 0.150dm3 • Step 2) Concentration = Mass / Volume • = 1.5 / 0.150 = 10g/dm3

9. Reactivity Series Reaction with acid Reaction with cold water How to extract Electrolysis Chemistry Revision Sheets - Topic 7 – Reactivity Series and Metal Extraction Reduction with carbon Unreactive Reduction with Carbon • Copper oxide + carbon → copper + carbon dioxide • 2CuO(s) + C(s) → 2Cu(l) + CO2(g) • This is displacement; the carbon has displaced the copper. • This is a redox reaction; the carbon has been oxidised and the copper has been reduced.

10. Aqueous – Cathode Rule Aqueous – Anode Rule At negative cathode, hydrogen is made, unless the metal present is less reactive than hydrogen. At positive anode, oxygen is made, unless there is a halogen present (Cl-, Br-or I-) Chemistry Revision Sheets - Topic 8 – Electrolysis Electrolyte must be molten or dissolved in water (aqueous) so that ions are free to move. In aqueous substances, hydrogen and hydroxide ions are formed by some water molecules breaking down. H2O  OH- + H+ As a solid (giant ionic lattice) ions are not free to move so this substance cannot conduct electricity. Half Equations Reduction at anode. e.g.) Cu2+ + 2e- Cu Copper ions have gained electrons to become copper element. Oxidation at cathode. e.g.) 2Cl- Cl2+ 2e- Chloride ions have lost electrons to become chlorine element. Oxygen production at cathode: Oxygen is produced in electrolysis of aqueous substances which don’t contain a halide ion: 4OH- O2 + 2H2O + 4e-

11. Strong Acids Fully dissociate in solution: Chemistry Revision Sheets - Topic 9 – Acids, Salts and Neutralisation Weak Acids Partially dissociate in water:

12. Reaction Profiles Endothermic Chemistry Revision Sheets - Topic 10 – Endothermic and Exothermic Exothermic How do we work out the overall energy change of a reaction? Work out the difference between the energy needed to break all the bonds in the reactants and the energy released to form all the bonds in the products.