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What colour does red litmus paper turn when dipped in lemon juice?
The lemon acid is going to change from either blue limtus paper to pink, or from pink limtus paper to blue, or blue litmus paper to purple , or/and pink litmus paper to purple.
Lemon juice contains citric acid so blue litmus paper dipped in lemon juice will turn red indicating that it is acidic.Blue litmus paper become red in acidic solutions (lemon juice contain citric...