Ans: The bond which is present in between ammonium and carbonate ion is an ionic bond. Inside the polyatomic ion, the covalent bond is present. In ammonium ion the covalent bond(dative covalent) is present. Here both the electrons are provided by nitrogen itself. Hence ammonium carbonate contains all the bonds. These bonds are ionic bond, covalent bond, and coordinate bond. The complete transfer of valence electrons between the atoms is called an ionic bond. The sharing of electron pairs between the atom is called a covalent bond. Such electron pairs are also known as shared pairs or bonding pairs. When both the electrons come from the same atom it is known as a coordinate bond. Hence all three bonds are present in (NH4)2CO3.