Question

define the term ionization enthalpy .discuss the affecting ionization enthalpy and its trends

Answer 1

Ionization enthalpy of elements refers to the total quantity of energy essential for an isolated gaseous atom to lose an electron in its ground state.

Losing of electrons results in the formation of cations.

It is measured in units of electron volts (eV) per atom or kilocalorie per mole or kilojoules per mole.

1 electron volt is the energy obtained by an electron while moving under a potential difference of 1 volt.

Factors on which Ionization Enthalpy depends on

Size of the atom:

Ionization enthalpy lessens as the atomic size gets higher.

As the distance of the outer electrons from the nucleus increases with increase the atomic radius, the attractive force on the outer electrons decreases.

Accordingly, outer electrons are held less firmly and for this reason, a lesser amount of energy is required to knock them out.

Nuclear charge:

The ionization enthalpy increases with increase in nuclear charge.

With the increase in nuclear charge, the electrons of the outer shell are more firmly held by the nucleus and thus greater energy is required to pull out an electron from the atom.

The ionization enthalpy increases as we move along a period from left to right due to increased nuclear charge.

The shielding effect of inner electrons:

As the shielding or screening effect of the inner electrons increases, the ionization enthalpy decreases.

Penetration effect of electrons:

Ionisation enthalpy increases as the penetration effect of the electrons increases

Effects of both half as well as completely filled orbitals.

General Periodic Trends

In a group, while moving from top to bottom it decreases.

It increases from left to right across a period.

Answer 2

ionization enthalpy the minimum energy to remove most losely bonded electron in an atom.
THERE ARE SOME FACTOR WHICH AFFECT I.P-
effective nuclear charge
penetration effect
shielding effect
size if atom
electronic configuration.ok