Answer:
We learnt that the symbol of elements indicate one atom. To represent one molecule of an element, we use a molecular formula. For example, a molecule of oxygen contains wo oxygen atoms, thus its molecular formula is 02. Here, the number below its symbol 2) stands for the number of oxygen atoms in a molecule of oxygen. Similarly, the olecules of hydrogen, nitrogen, chlorine are H2, N2 and Clz respectively. Thus, the olecular formula of an element is defined as the symbolic representation bondshich shows the actual number of atoms in one molecule of the element.