Q11 of 34 Page 34

Fresh milk has a pH of 6. How do you think the pH will change as it turns into curd? Explain your answer.

The pH of fresh milk is 6. As milk turns into curd, lactic acid is formed due to which it become more acidic. Therefore, the pH of milk will reduce.

As the milk turns into curd, its pH will fall below 6 (it will become more acidic). This is because an acid (lactic acid) is produced when milk turns into curd.


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(a) Which solution is (i) neutral (ii) strongly alkaline (iii) strongly acidic (iv) weakly acidic, and (v) weakly alkaline?


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(a) Why does he shift the pH of the fresh milk from 6 to slightly alkaline?


(b) Why does this milk take a longer time to set as curd?

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