Chemistry Chapter 4 – Chemical changes – reactivity series, reduction and oxidation Write the reactivity series in order from most reactive to the least reactive. Describe how we use reduction to extract metals from the reactivity series. State the metals can be reduced using carbon. Describe what reduction and oxidation in in term of oxygen. HIGHER TIER ONLY: Describe what oxidation and reduction are in terms of electrons. HIGHER TIER ONLY: Write the ionic equation to show the reaction between magnesium and copper chloride solution. HIGHER TIER ONLY: Write the half equation for the extraction of iron. Describe which metals will react with water and acid and how violent this reaction is. Complete the table to show which reactions will results in a positive displacement reaction. Represent this with ticks and crosses. HIGHER TIER ONLY: Write the half equation to show the reaction between magnesium and copper chloride solution. HIGHER TIER ONLY: Write the ionic equation to show potassium and magnesium forming positive ions. Solution used Metal being added Magnesium Zinc Iron Copper Magnesium sulphate Zinc sulphate Iron sulphate Copper sulphate Describe why sodium is more reactive than lithium. HIGHER TIER ONLY: Identify from these two half equations which is oxidised and which is reduced. Al – 3e-  Al3+ Cr3+ + 3e-  Cr HIGHER TIER ONLY: Write the balanced ionic equation for the extraction of zinc.

Chemistry Chapter 4 – Chemical changes – metals and acid, soluble salts, neutralisation, pH and strong and weak acids Write the general word equations for the reactions below: Metal + acid  Acid + base  Metal oxide + acid  Metal hydroxide + acid  Metal carbonate + acid  Describe how we make a soluble salt from an insoluble solid substance . Describe what neutralisation is and include the equation. State 2 methods we could use to identify the pH of a substance. Identify from the formula the acid and write what salts are formed from using them. HCl H2SO4 HNO3 Define the terms: Acid – Base – Alkali - HIGHER TIER ONLY: Describe the difference between a weak and strong acid and give examples of common acids. Describe how to make a crystalised salt from using a metal and acid. HIGHER TIER ONLY: Describe what happens as the pH decreases by one unit to the concentration of hydrogen ions. Conc and weak acid : The strength of an acid is a measure of the degree of its ionisation - strong acids are fully ionised but weak acids are only partly ionised. Remember that the opposite of strong is weak. The concentration of an acid is a measure of the number of moles of acid in 1 dm3 of acid solution. For example, 2 mol/dm3 hydrochloric acid is twice as concentrated as 1 mol/dm3 hydrochloric acid or 1 mol/dm3 ethanoic acid. Remember: the opposite of concentrated is dilute. Using the pH scale below identify what is an acid, alkali and neutral. HIGHER TIER ONLY: Describe what redox reaction is and write the half equation for the reaction iron and sulphuric acid. HIGHER TIER ONLY: Describe what concentration is and link this to how we can have a weak but concentrated acid.

Chemistry Chapter 4 – Chemical changes – electrolysis Describe what electrolysis is. Describe what a simple binary electrolyte is and the state they need to be in for electrolysis to happen. Complete the below: If the ions are halogens then the ………………… is produced. If the ions are not halogens then ……..……. is produced because …………… ion is discharged. If the ions are above hydrogen in the reactivity series then ………………………. is produced. If the ions are below hydrogen in the reactivity series then ………………………. is produced. State what the ore of aluminium oxide is called and explain why we mix this will cryolite. Label the set up below using the keywords: electrolyte, cation, cathode, anion, anode, D.C power supply and electrode. Draw an arrow to show where the cation and anion migrate to. Label the below image for the electrolysis of aluminium oxide. HIGHER TIER ONLY: Write the half equation for the electrolysis molten copper bromide. HIGHER TIER ONLY: Describe what OILRIG is. Describe what a preferential discharge is. HIGHER TIER ONLY: Describe which electrode oxidation and reduction occurs during electrolysis. Explain why the carbon anodes need replacing continuously. At the cathode: At the anode : 2H+ + 2e– → H2 4OH– – 4e– → 2H2O + O2 Describe what will be discharged at the cathode and anode during the electrolysis of copper sulphate. HIGHER TIER ONLY: Write the half equation for the electrolysis of sodium chloride solution. HIGHER TIER ONLY: Write the half equations at the cathode and anode for the electrolysis of dilute sodium sulphate solution. HIGHER TIER ONLY: Write the half equations at the cathode and anode for the electrolysis of aluminium oxide.

Chemistry Chapter 4 – Chemical changes – required practical x 2 and maths skills Describe what order of magnitude is. Describe a method used to prepare a pure, dry sample of a soluble salt from an insoluble oxide or carbonate. Draw a diagram to show the set up for the electrolysis of sodium chloride, sodium sulphate, copper (II) chloride and copper (II) sulphate. Independent variable – Dependent variable – Control variables – Complete the below table: Conc. of acid in mol/dm3 Conc. of acid in standard form mol/dm3 pH 0.1 1 0.01 0.001 0.0001 0.00001 0.000001 0.0000001 State the result you would expect to see for the electrolysis practical and explain why you would expect to see this. that an order of magnitude is when something increases or decreases by a factor of ten. Write the variables for the practical for making a pure, dry salt. Independent variable – Dependent variable – Control variables – Explain how to make a purer sample of your salt and why we add the metal in excess. Write a risk assessment for this practical. Include the risk, hazard and control for at least 1 risk.