Difference between revisions of "Indicator (Chemistry)"
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==Key Stage 3== | ==Key Stage 3== | ||
===Meaning=== | ===Meaning=== | ||
| − | An '''indicator''' is a [[dye]] that changes [[colour]] | + | An '''indicator''' is a [[dye]] that changes [[colour]] when other [[chemical]]s are present. |
===About Indicators=== | ===About Indicators=== | ||
| − | : The [[colour]] of | + | : Some [[indicator]]s detect [[pH]] but others can be used to detect other [[chemical]]s. |
| + | Some non-pH '''indicators''' you should know: | ||
| + | *[[Iodine Solution]] - Used to detect starch. | ||
| + | *[[Biuret Solution]] - Used to detect proteins. | ||
| + | *[[Benedict's Solution]] - Used to detect simple [[sugar]]s like [[glucose]]. | ||
| + | |||
| + | ===About pH Indicators=== | ||
| + | : The [[colour]] of a '''pH indicator''' can be used to tell the [[pH]] of a [[solution]]. | ||
: Different '''indicators''' will have a different range of colours for different [[pH]] values. | : Different '''indicators''' will have a different range of colours for different [[pH]] values. | ||
: A good '''indicator''' can be added to [[solution]] without affecting the [[pH]] of the [[solution]]. If an '''indicator''' change the [[pH]] of a [[solution]] it could not give an [[accurate]] [[reading]]. | : A good '''indicator''' can be added to [[solution]] without affecting the [[pH]] of the [[solution]]. If an '''indicator''' change the [[pH]] of a [[solution]] it could not give an [[accurate]] [[reading]]. | ||
| − | Some '''indicators''' you should know: | + | Some '''pH indicators''' you should know: |
*[[Litmus Paper]] | *[[Litmus Paper]] | ||
*[[Red Cabbage Indicator]] | *[[Red Cabbage Indicator]] | ||
Revision as of 16:50, 3 December 2018
Key Stage 3
Meaning
An indicator is a dye that changes colour when other chemicals are present.
About Indicators
- Some indicators detect pH but others can be used to detect other chemicals.
Some non-pH indicators you should know:
- Iodine Solution - Used to detect starch.
- Biuret Solution - Used to detect proteins.
- Benedict's Solution - Used to detect simple sugars like glucose.
About pH Indicators
- The colour of a pH indicator can be used to tell the pH of a solution.
- Different indicators will have a different range of colours for different pH values.
- A good indicator can be added to solution without affecting the pH of the solution. If an indicator change the pH of a solution it could not give an accurate reading.
Some pH indicators you should know:
- Litmus Paper
- Red Cabbage Indicator
- Universal Indicator
- Phenolphthalein
- Methyl Orange
- Bromothymol Blue
Examples
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