Question

What is common to the changes mentioned below.
the setting of milk into curd; the rusting of iron; the ripening of a mango
(a) They are all reversible changes.
(b) They are slow reversible changes.
(c) They are fast reversible changes.
(d) They are slow irreversible changes.

Answer 1

(d) They are slow irreversible changes.
Curd cannot be converted back into milk, ripened mango cannot turn raw, and rusting of iron cannot be reverted back. Therefore, they all are irreversible reactions.