Science at key stage 3    (Year 9)

• describe how metals change due to exposure to the air, eg iron rusts, silver becomes dull, copper darkens
• identify some metals that corrode readily and some that do not
• give a reason why sodium, potassium and lithium seem to be metals, eg they are shiny, and a reason why they seem not to be, eg they are not hard, they can't be left in the air without tarnishing

• identify evidence for a chemical reaction, eg bubbles of gas, heat produced
• describe some similarities in the reactions, eg hydrogen produced, pH shows alkali produced
• describe differences between the reactions, eg flame produced with potassium but not with sodium or lithium
• identify an order of reactivity of the metals
• describe and explain some of the safety precautions to be taken when dealing with reactive metals

• identify relevant observations, eg extent of bubbling, rise in temperature
• use observations to suggest an order of reactivity

• use the reactivity series to make a sensible prediction, eg sodium would be more reactive with oxygen than copper
• evaluate the evidence obtained, eg magnesium reacted more violently than copper, but it was difficult to compare sodium and calcium
• state that all the metals tested produced oxides

• identify where reactions occur and where they do not
• relate their results to the position of the metal in the reactivity series
• articulate the pattern, eg it's the metal that's important; a metal high in the reactivity series will push out one lower down, but a lower one won't push out a higher one
• use an analogy or model to explain the results, eg the zinc has a stronger pull on the sulphate than the copper does

• explain that energy released by the reaction is sufficient to melt the iron
• describe how molten iron is used in welding, eg on railway lines

• summarise reactions of metals, making use of patterns in the reactivity series
• use the activity series to make predictions about the reactions of metals
• identify where an element cannot be given a position or where a firm prediction cannot be made, giving reasons for the difficulty

• identify key points relevant to the questions asked
• make connections between reactivity and aspects of use, eg aluminium is reactive, and therefore hard to extract - this is why it wasn't used as early as iron

• identify a workable procedure, eg to measure the temperature of the reacting mixture every minute for 10 minutes
• identify variables that need to be controlled, eg quantity of metal, volume of acid
• present results clearly and appropriately
• explain the results obtained in the light of the reactivity series and knowledge about aluminium

• recall key ideas about the relative reactivity of different metals
• use and apply these ideas in different contexts
• identify how sample answers provide, or do not provide, the information required