Question

The second ionization potential of an element M is the energy required to:
A.Remove one mole of electron from one mole of gaseous anion
B.Remove one mole of electron from the one mole of gaseous cation of the element
C.Remove one mole of electron from the one mole of monovalent gaseous cation of the element
D.Remove 2 mole of electron from one mole of gaseous atoms

Answer 1

Hint: Ionization energy involves removal of one electron from an atom. An atom after first ionization becomes gaseous cation and thereby second ionization energy is removal of electrons from monovalent gaseous cation.

Complete answer:
Ionisation potential is also known as ionization energy. It is defined as the minimum energy required to remove the most loosely bounded outermost shell electron in ground state from an isolated gaseous atom. Isolated atom means an atom without bonding with another atom. Electrons cannot be removed from the solid state of an atom, so, it has to convert it into a gaseous atom. Ionization energy is always an endothermic process which means this process always requires energy and does not evolve energy. An atom with more attractive force of nucleus to the outermost shell electron requires more amount of ionization energy in order to overcome attraction force by the nucleus. Successive ionization energy is defined for an atom undergoing several times ionization. The first ionization energy of an element is defined as removal of one mole of electrons from one mole of isolated gaseous atoms which does not have any charge. Second ionization energy can be defined as the removal of one mole of electron from the one mole of monovalent gaseous cation of the element as after first ionization process, the metal forms an isolated monovalent gaseous cation due to loss of one electron from the atom.
Successive ionization energies for an atom M are as follow:
$${\text{M}}_{\left(\text{g}\right)}+{\text{E}}_1\to {\text{M}}_{\left(\text{g}\right)}^{+}+{\text{e}}^{-}$$ where, $${\text{E}}_1$$ is first ionization energy for atom M.
$${\text{M}}_{\left(\text{g}\right)}^{+}+{\text{E}}_2\to {\text{M}}_{\left(\text{g}\right)}^{+2}+{\text{e}}^{-}$$ where, $${\text{E}}_2$$ is second ionization energy for atom M.
Similarly, $${\text{M}}_{\left(\text{g}\right)}^{+2}+{\text{E}}_3\to {\text{M}}_{\left(\text{g}\right)}^{+3}+{\text{e}}^{-}$$ where, $${\text{E}}_3$$ is third ionization energy for atom M.

Thus, the correct option is C.

Note:
Electron affinity or electron gain enthalpy is the amount of energy released when an electron is added to the valence shell of an isolated gaseous atom. Generally first electron addition is an exothermic process and second ionization energy is always an endothermic process due to inter electronic repulsion.