TYCES – Year 10 Chemistry Summer Work 2023 Aims: 1) To test knowledge of reversible reactions and equilibrium. 2) To learn about REDOX reactions using prior knowledge from electrolysis and formula. 3) To test knowledge of REDOX reactions 4) Develop research and revision skills. Equilibrium Past Paper Questions Forward The rates reaction are and backward reaction are The equilibrium yields of SO2 increase. happening Equilibrium moves to the left and O2 hand side in the endothermic directionteam isson increases. Equilibrium moves to the the fewest gaseous atthe the same and concentration constant. Same time right molecules to hand side to the side with oppose the change. ! The Equilibrium direction to equilibrium yield of NHS moves to the right hand side in increases. the exothermic oppee the change. The equilibrium Equilibrium moves to the highest gaseous molecules left to yields of N2 hand side oppose the and He increases. to the side change - with - - a substance that increases the rate but itself remains unchanged of a at the end chemical reaction of the reaction. decreases decreases decreases. decreases. IGCSE REDOX Notes ● Oxidation is gain of oxygen ● Reduction is loss of oxygen ● Roman numerals are used after an element in the name of a compound to refer to its oxidation state – normally used in reference to metals showing what + charge they have o E.g.,iron (II) is Fe , iron (III) is Fe , copper (II) is Cu , manganate (VII) is Mn etc... 2+ 3+ 7+ (Extended only) Define redox in terms of electron transfer ● Oxidation Is Loss (of electrons) ● Reduction Is Gain (of electrons) 2+ A redox reaction is one where both oxidation and reduction take place. If an element is gaining electrons and another is losing electrons, then the reaction is a redox reaction (or losing/gaining oxygen) Potassium manganate (VII): o Deep purple and when reduced, it becomes colourless o E.g., react with iron (II) chloride and colourless Mn ions are formed o E.g., react with sulphur dioxide and the same thing happens. o This is because, potassium manganate (VII) is an oxidising agent and therefore is reduced itself. 2+ REDOX past paper questions: A. B A D D - A C A I B - A C A B A A C R D D A