pH and indicators
The resources in this list allow students to investigate the pH scale, acidity, alkalinity, and indicators. This is often students' first chance to get hands on with chemistry in Year 7 and always creates a bit of a buzz in the classroom. The list provides a range of activities, lesson ideas, film clips, background information and practical tips.
The resources are linked to these topics:
- defining acids and alkalis in terms of neutralisation reactions
- the pH scale for measuring acidity/alkalinity; and indicators
- reactions of acids with metals to produce a salt plus hydrogen
- reactions of acids with alkalis to produce a salt plus water
Visit the secondary science webpage to access all lists: www.nationalstemcentre.org.uk/secondaryscience
Whilst this list provides a source of information and ideas for experimental work, it is important to note that recommendations can date very quickly. Do NOT follow suggestions which conflict with current advice from CLEAPSS, SSERC or recent safety guides. eLibrary users are responsible for ensuring that any activity, including practical work, which they carry out is consistent with current regulations related to health and safety and that they carry an appropriate risk assessment. Further information is provided in our Health and Safety guidance.
Stings and Things: an Investigation into pH
A good practical investigation that looks at acids and alkalis in the context of nettle stings. Students look at nettles to see how they sting, test everyday substances of pH and then test the pH of nettle venom and dock leaf sap.
Indicators in Chemistry
A smashing lesson starter that is highly recommended. The introduction will really get students thinking and make them want to know more. It then leads very well into students' own practical work where they try to form solutions the same colour as the traffic lights, red, green and orange.
Make Your Own Indicator
An interesting article that outlines how to make and use a red cabbage indicator and suggestions for other plants that could be used as indicators.
Teaching Ideas and Evidence in Science at Key Stage 3
This is a series of activities aimed to develop understanding and explore acids and alkalis. There are teacher notes and student worksheets included.
This resource is in the form of a website so after reaching the webpage click on the 'topics index' tab at the top and then choose 'acids and alkalis' which is topic N.
World Oceans Day *suitable for home teaching*
This is a topical set of activities that looks at acids in the context of acidification of the oceans. There are three activities: ocean acidification in a cup, dissolving eggshells in vinegar, and marine food webs, all with lesson plans and student worksheets.
Dry Ice Demonstration
This video demonstrates an experiment using solid carbon dioxide (dry ice) and sodium hydroxide which is likely to impress students. The clip shows how solid carbon dioxide sublimes into gaseous carbon dioxide. The video is accompanied by an information sheet which summarises the requirements, procedure and scientific background to the experiment.
London U.K. - Dissolving: The Acid Bath Murderer
A gruesome investigation, linked to a crime in the 1940s, to see whether acids or alkalis are more effective at dissolving meat and bone.
RADAAR framework to support the pH Scale
This infographic uses the RADAAR (research, anticipate, diagnose, address, assess, review) framework developed by the Best Evidence Science Teaching (BEST) project, to guide teachers through teaching the topic of the pH scale to 11 to 14 year olds. It looks at how to establish students' misconceptions, how to address them and then build on understanding.
