Learner Resource 1
Introduction
You will be given one or more worksheets to complete to describe a particular type of acid–base
titration. For each worksheet, complete the following steps:
1. Sketch the appropriate pH curve for the titration.
2. Select the correct answers to complete the description of the position of the equivalence
point.
3. Suggest one or more appropriate indicators.
4. On your graph, label the pH range of the selected indicator(s). This is the pH range within
which the indicator changes colour.
5. Colour the graphs to show the colours the solution will be across the pH range the selected
indicator. If you have chosen more than one indicator for a particular titration, just choose
one indicator to colour.
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pH and Buffers
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© OCR 2016
Strong alkali added to strong acid
The equivalence point is high on / low on / in the middle of the pH scale. (delete as appropriate)
Indicator(s): ………………………………………..
pH
volume of alkali added
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pH and Buffers
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© OCR 2016
Strong alkali added to weak acid
The equivalence point is high on / low on / in the middle of the pH scale. (delete as appropriate)
Indicator(s): ………………………………………..
pH
volume of alkali added
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pH and Buffers
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© OCR 2016
Weak alkali added to strong acid
The equivalence point is high on / low on / in the middle of the pH scale. (delete as appropriate)
Indicator(s): ………………………………………..
pH
volume of alkali added
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pH and Buffers
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© OCR 2016
Weak alkali added to weak acid
The equivalence point is high on / low on / in the middle of the pH scale. (delete as appropriate)
Indicator(s): ………………………………………..
pH
volume of alkali added
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pH and Buffers
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© OCR 2016