Give reasons for the following:
$(i)$ Moist air and acidic gases are not good for some metals.
$(ii)$ Chips manufacturers usually flush bags of chips with nitrogen gas.

(N/A) $(i)$ Moist air leads to the corrosion of metals like iron (rusting),while acidic gases react with metals like copper and silver,causing them to tarnish or corrode.
$(ii)$ Nitrogen is an inert gas. By flushing the bags with nitrogen,manufacturers displace oxygen,which prevents the oxidation of fats and oils in the chips,thereby keeping them fresh and preventing rancidity.