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Explain how alkalis affect indicators such as litmus and methyl orange.

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Cambridge IGCSE Combined ScienceAcids, bases and saltsCore content

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Explain how alkalis affect indicators such as litmus and methyl orange

This point belongs to The characteristic properties of acids and bases, especially The characteristic properties of acids and bases outcomes.
You need to be able to explain how alkalis affect indicators such as litmus and methyl orange.
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DescribeExplain

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Paper 3 structured question: The characteristic properties of acids and bases

Paper 3Theory (Core)3 marks

Description

Indicators and pH

Indicators such as litmus and methyl orange are commonly used to test the acidity or basicity of solutions. Litmus paper turns blue in alkaline solutions, while methyl orange changes from red to yellow in the presence of alkalis.

a
Explain how alkalis affect indicators like litmus and methyl orange.
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