GCSE Chemistry C3 - Electrolysis 4.0 / 5 based on 4 ratings ? ChemistryElectrolysisGCSEEdexcel Created by: BethanyMCreated on: 15-06-15 20:07 What is electrolysis? The process which ionic substances are broken down into simpler substances using electricity. Gases or metals may form at the electrodes. 1 of 27 Is the current supplied in electrolysis direct or alternating? Direct 2 of 27 What is the electrolyte? An ionic substance in the molten state or dissolved in water 3 of 27 What are the anode and the cathode? The anode is the positively charged electrode, the cathode is the negatively charged electrode 4 of 27 Where do positively charged ions (the cations) migrate to in electrolysis? Positively charged cations migrate to the negatively charged cathode 5 of 27 Where do negatively charged ions (the anions) migrate to in electrolysis? Negatively charged anions migrate to the positively charged anode 6 of 27 Define oxidation The loss of electrons 7 of 27 Define reduction The gain of electrons 8 of 27 In electrolysis, where does oxidation occur? At the anode 9 of 27 In electrolysis, where does reduction occur? At the cathode 10 of 27 What are the products of the electrolysis of sodium chloride (l)? Sodium and chloride 11 of 27 What is the half equation at the cathode? Na+ + e- = Na 12 of 27 What is the half equation at the anode? 2Cl- = Cl2 + 2e- 13 of 27 What can sodium (Na) be used for? Street lamps and coolant for nuclear reactors 14 of 27 What are the products of the electrolysis of sodium chloride (aq)? Hydrogen, chlorine and sodium chloride (aq) 15 of 27 What are the products of the electrolysis of lead bromide (l)? Lead and bromine 16 of 27 What are the products of the electrolysis of copper sulphate (aq)? Copper and oxygen 17 of 27 What are the products of the electrolysis of copper chloride (aq)? Copper and chlorine 18 of 27 What are the products of the electrolysis of sodium sulphate (aq)? Hydrogen and oxygen 19 of 27 When purifying copper, is the impure copper on the anode or cathode? The anode (positive electrode) 20 of 27 When purifying copper, is the pure copper on the anode or cathode? The cathode (negative electrode) 21 of 27 What is the electrolyte made of in the purification of copper? A solution of copper sulphate containing copper ions 22 of 27 Which electrode gains mass in the process of copper purification? The cathode 23 of 27 What is the half equation for the reaction at the anode in the electrolytic purification of copper? Cu (s) = Cu2+ (aq) + 2e- 24 of 27 What is the half equation for the reaction at the cathode in the electrolytic purification of copper? Cu2+ (aq) + 2e- = Cu (s) 25 of 27 What happens to the impurities when impure copper is purified by electrolysis? Precious metals such as gold, silver and platinum are recovered from them 26 of 27 Why is electroplating objects with metal useful? It prevents corrosion and improves the appearance of objects (it decorates them) 27 of 27
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