Question

a milk man added a small amount of baking soda to fresh milk .(a)why does he the slightly alkaline ?(b) why does this milk take a longer time to set as a curd ?

Answer 1

a) By adding a very small amount of baking soda to fresh milk, the milkman keeps the milk unspoiled for little more time than usual time.
As the pH value increases the milk turns to slightly alkaline,
b) As baking soda is added, it turned into a base. But curd needs acidic condition to set. Hence this milk takes a long time to set as a curd.
hope it helps

Answer 2

A milkman do that so that the lactic acid which is formed in the milk firstly neutralise the base (baking soda) .so that it take long time to convert milk into curd.