Answer:
1. A chemical reaction represents a change in the distribution of atoms, but not in the number of atoms. In this reaction, and in most chemical reactions, bonds are broken in the reactants (here, Cr–O and N–H bonds), and new bonds are formed to create the products (here, O–H and N≡N bonds).
2.We balance chemical equations due to the law of conservation of mass, which states that mass can neither be created or destroyed. Therefore, in a chemical reaction, the total mass of the reactants must be equal to the total mass of the products.
3.In ionic bonding, atoms transfer electrons to each other. Ionic bonds require at least one electron donor and one electron acceptor. In contrast, atoms with the same electronegativity share electrons in covalent bonds, because neither atom preferentially attracts or repels the shared electrons.
