Seema bought a chips packet and opened it. Suddenly her friend Shanu came

Seema bought a chips packet and opened it. Suddenly her friend Shanu came. She started playing and forgot to eat the chips. On the next day, when she eat the chips, she felt the taste was not good and her health fell down. She told her mother to take her to a doctor. The doctor told them this is because of eating rancid chips. He gave medicines, by which Seema became well within a few days.
Read the above passage and answer the following questions:
(i) Why does chips remain fresh for a longer time in a sealed packet?
(ii) Why did chips of an open packet become rancid?
(iii) What value do you infer from this passage?

(i) Chips remain fresh for a longer time in sealed packet because the sealed packet contains an inert gas (generally nitrogen or helium), which prevents the oxidation of fats and oils of the chips.
(ii) Chips of an open packet becomes rancid because of the oxidation of fat and oil of the chips (food) by oxygen of air.
(iii) The value inferred from this passage is that a food (junk food) kept open for a longer time should not be eaten.