Write the number of valence electrons present in a nitrogen atom $(\frac{14}{7} \text{N})$.

In the context of chemical reactions, as mentioned in Section 1.2 of the text, reactions involve the breaking and making of bonds between atoms. These bonds are formed using valence electrons. For Nitrogen, with an atomic number of 7, the first shell ($K$) holds 2 electrons, and the second shell ($L$) holds the remaining 5. These 5 electrons in the outermost shell are the valence electrons available for chemical bonding.