The compounds containing coordinate covalent bonds are called coordinate compounds.
(a) Physical state - These compounds exist as gases, liquids or solids.
(b) Electrical conductivity - Like covalent compounds, co-ordinate compounds also do not contain charged particles (ions), so they are bad conductors of electricity.
(c) Melting point - These compounds have melting and boiling points higher than those of purely covalent compounds but lower than those of purely ionic compounds.
(d) Solubility - Insoluble in polar solvents like water but are soluble in non-polar solvents like benzene, CCI_4, and toluene.
(e) Reactions - Coordinate covalent compounds undergo molecular reactions which are slow.

(a) Like covalent compounds, coordinate compounds also do not contain charged particles (ions) so they are bad conductors of electricity.
(b) Ionic bond is a strong bond when compared to Hydrogen bond.
(c) Ionic or electrovalent bonds are formed by transfer of electrons between atom.
(e) The electron which are involved in bonding are called valence electrons.

In ionic bond formation the bond is formed between the oppositely charged ions and these ions come closer to each other due to electrostatic force of attraction. So ionic bond is also called electrostatic bond

Both the oxidation and reduction occurs in the same reaction simultaneously is known as redox reaction. If one reactant gets oxidised, the other gets reduced. Such reactions are called oxidation-reduction reactions or redox reactions
Ex. 1 : 2 PbO + C \(\rightarrow\) 2 Pb + CO₂
Ex.2: Zn + CuSO₄\(\rightarrow\) Cu + ZnSO₄

Bond which is formed between atoms by the mutual sharing of electrons is known as covalent bond.

Kossel - Lewis theory is based on the concept of electronic configuration of noble gases.

A chemical bond may be defined as the force of attraction between the two atoms that binds them together as a unit called molecule