Quiz 2: Lifes Chemical Basis


The most abundant molecule found in living things is water (H ₂ O). As carbon, nitrogen, hydrogen and oxygen are the most abundant in living things but all these are atoms not molecules. Water forms around most part of living things. As in humans itself it formed around 70% of body weight. Almost all the chemical reactions in life processes occur in solution of water. Thus it is well documented that water is most abundant of all and life depends on water.

This is not true for all the atoms because there is one exception i.e. hydrogen. It is having only proton and electron. There is no neutron in case of hydrogen atom. Hence statement is false that every atom consists of proton, neutron and electron.

Ozone is strong oxidising agent. Ozone formation is endothermic reaction i.e. it requires energy. But when ozone gets breakup it releases energy i.e. exothermic reaction and makes it stable by giving oxygen atom and releases oxygen gas. As we know our atmosphere is having oxidising nature so when ozone comes in contact with our atmosphere it gets oxidised due to unstable oxygen atom attached to it. Third oxygen atom attached to ozone did not require any energy to breakup so due to highly oxidising nature of ozone it is highly reactive.

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