from a site that is not contaminated to need and with animal waste or other pollutants. problems that might occur for Explaining: Liebig condenser each of the Demonstrate the distillation of dirty methods (or inky) water, using a Liebig suggested. condenser. Plenary: Thinking skills Plus, Minus, Interesting: We should get all our drinking water by distilling sea water (Possible answers: Plus – there should never be a problem of running out of water; Minus places – not by the sea would have to transport the sea water somehow; Interesting would this affect marine – environments? Thames Water has built a desalination plant in the Thames.) Lesson 7Fb: Indicators Learning objectives Exemplar teaching activities Differentiation Resources skills Practical skills Developing Starter: Water into Exploring: Using Resources n/a A two-part ‘wine’ Recall examples of everyday demonstration red cabbage as from 7Fb practical: substances that are alkalis. Demonstrate the into wine’ an indicator Exploring students first ‘water Recall the colour changes associated trick. Pour a beaker of (in fact Students could Science. extract the ‘water’ with litmus indicator. dilute sodium hydroxide solution) into use other fruit or colour from red Describe how indicators are used to an apparently empty beaker (which vegetables and cabbage leaves distinguish between acidic, alkaline has a few drops of phenolphthalein assess them for by crushing, and neutral solutions. indicator at the bottom of the their usefulness dissolving and Securing beaker). as indicators. filtering. The Use solutions of known solution acidity/alkalinity in order to deduce a Exploring: Using red cabbage as an obtained from colour chart for an indicator. indicator this process is then used to
from a site that is not contaminated with animal waste or other pollutants. Explaining: Liebig condenser Demonstrate the distillation of dirty (or inky) water, using a Liebig condenser. Plenary: Thinking skills Plus, Minus, Interesting: We should get all our drinking water by distilling sea water (Possible answers: Plus – there should never be a problem of running out of water; Minus – places not by the sea would have to transport the sea water somehow; Interesting – would this affect marine environments? Thames Water has built a desalination plant in the Thames.) to need and problems that might occur for each of the methods suggested. Lesson 7Fb: Indicators Learning objectives Exemplar teaching activities Differentiation Resources skills Practical skills Developing Recall examples of everyday substances that are alkalis. Recall the colour changes associated with litmus indicator. Describe how indicators are used to distinguish between acidic, alkaline and neutral solutions. Securing Use solutions of known acidity/alkalinity in order to deduce a colour chart for an indicator. Starter: Water into ‘wine’ demonstration Demonstrate the ‘water into wine’ trick. Pour a beaker of ‘water’ (in fact dilute sodium hydroxide solution) into an apparently empty beaker (which has a few drops of phenolphthalein indicator at the bottom of the beaker). Exploring: Using red cabbage as an indicator Exploring: Using red cabbage as an indicator Students could use other fruit or vegetables and assess them for their usefulness as indicators. Resources from 7Fb Exploring Science. n/a A two-part practical: students first extract the colour from red cabbage leaves by crushing, dissolving and filtering. The solution obtained from this process is then used to