Q.Among the following, the compound that contains, ionic, covalent and co-ordinate linkage is :

NH4Cl is the only listed compound that simultaneously contains an ionic bond, ordinary covalent bonds, and a coordinate (dative) bond.

Check each option for the three bond types (ionic, covalent, coordinate):

1. NH3 (ammonia): only covalent N-H bonds (formed by mutual sharing of electrons between N and 3 H). No ionic bond, no coordinate bond.
2. NaCl: purely ionic — Na+ transfers an electron to Cl- and the two ions attract electrostatically. No covalent or coordinate bond.
3. NH4Cl (ammonium chloride): built in two stages.
   • First, NH3 (three covalent N-H bonds, N still has one lone pair) reacts with HCl. The nitrogen lone pair is donated into the empty orbital of H+ (from HCl), forming a fourth N-H bond where BOTH electrons come from nitrogen alone — this is a coordinate (dative) covalent bond, giving the NH4+ ion. …

CuSO4·5H2O has all three bond types: ionic (Cu²⁺–SO4²⁻), covalent (within SO4²⁻), and coordinate (Cu²⁺–H2O).

In CuSO4·5H2O: the bond between the Cu²⁺ cation and the sulphate (SO4²⁻) anion is electrovalent (ionic); the S–O bonds within the sulphate ion itself are covalent; and four of the five water molecules are bonded to Cu²⁺ through coordinate (dative) covalent bo …