n factor of base=acidity of base

Acidity =no. of OH^- replacable ion

the n factors of NaOH =1

since it has 1 OH^- replacable ion.

Dipole moment of NH₃ is higher than NF₃ molecule. This is due to the fact that dipole moment is a vector quantity and hence resultant dipole moment in a molecule will depend upon the direction of dipole moments of individual bonds. Nitrogen has a lone pair of electrons and is more electronegative than hydrogen. So, in case of NH₃, the orbital moment due to the lone pair of electrons on nitrogen is in the direction of lone pair of electrons is in the same direction of the 3 N-H dipoles. Thus, the molecule has a net dipole moment and it is polar.

In NF₃, Florine being more electronegative than Nitrogen pulls the shared pair of electrons of the N-F bonds towards itself. Because of this, the orbital moment due to lone pair of electrons and the resultant dipole moment of 3 N-F bonds point in the opposite directions to that of lone pair of electrons. This lowers the dipole moment of NF₃.

In both molecules i.e., NH₃ and NF₃, the central atom (N) has a lone pair electron and there are three bond pairs. Hence, both molecules have a pyramidal shape. Since fluorine is more electronegative than hydrogen, it is expected that the net dipole moment of NF₃ is greater than NH₃. However, the net dipole moment of NH₃ (1.46 D) is greater than that of NF₃ (0.24 D).

Since in case of  NF₃ , fluorine is more electronegative than nitrogen, so it will attract the shared pair of electron towards itself from nitrogen. As a result dipole due to all F is in opposite direction to the resultant dipole due to N-F bonds,therefore the net dipole decreases.

In NH₃, Nitrogen is more electronegative than H, so it will attract the shared pair of electrons towards itself.As  a result dipole due to Nitrogen is in same direction as the resultant dipole moment due to N-H bond& hence the net dipole increases.

Hence, the net dipole moment of NF₃ is less than that of NH₃.

The mole is the amount of a substance of a system which contains as many elementary entities as there are atoms in 0.012 kilogram of carbon-12; its symbol is "mol."The mole is widely used in chemistry as a convenient way to express amounts of reactants and products of chemical reactions.

For example, the chemical equation 2 H₂ + O₂ → 2 H₂O implies that 2 moles of dihydrogen (H₂) and 1 mole of dioxygen (O₂) react to form 2 moles of water (H₂O). The mole may also be used to express the number of atoms, ions, or other elementary entities in a given sample of any substance. The concentration of a solution is commonly expressed by its molarity, defined as the number of moles of the dissolved substance per litre of solution.

7.4

The electrons hover around the nucleus in diffuse cloud-like waves, known as orbitals, that describe only the probability of finding the electron at different places within the atom. But those orbitals can combine to form a clump-like “wave packet” that contains the electrons and does orbit the nucleus like a planet.

The polarity of a bond is the distribution of electrical charge over the atoms joined by the bond. While bonds between identical atoms (as in H₂) are electrically uniform in the sense that both hydrogen atoms are electrically neutral, bonds between atoms of different elements are electrically inequivalent.

In hydrogen chloride, for example, the hydrogen atom is slightly positively charged whereas the chlorine atom is slightly negatively charged. The slight electrical charges on dissimilar atoms are called partial charges, and the presence of partial charges signifies the occurrence of a polar bond.