Question

why does the colour of onion changes when we add vinegar to it

Answer 1

The color of onion changes when we add vinegar to it since the vinegar is acidic in nature it changes the ph  of solution when it is mixed with onion . The color of solution will depend upon how much and in which acidic vinegar is mixed if it gives a combine ph less than 7 then it shows red color and when ph is more than  7 it show blue color .

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