Question

Why should curd and sour substance not be kept in a brass and copper container?

Answer 1

Beacause curd and sour subatances are acidic in nature so they react with these metals and form poisonous compounds

Answer 2

$<i><v> Curd and other sour substances contain acids. Therefore, when they are kept in brass and copper vessels, the metal reacts with the acid to liberate hydrogen gas and harmful products, thereby spoiling the food.$