Periodic Trends in Properties of Elements

What are isoelectronic ions? Give examples.

Explain the following, give an appropriate reason.

First ionisation potential of the C-atom is greater than that of the B atom, whereas the reverse is true is for the second ionisation potential.

Energy of an electron in the ground state of the hydrogen atom is −2.18 × 10⁻¹⁸ J. Calculate the ionisation enthalpy of atomic hydrogen in terms of kJ mol⁻¹.

In what period and group will an element with Z = 118 will be present?

Which of the following orders of ionic radii is correct?

Explain the Pauling method for the determination of ionic radius.

The First ionisation potential of Na, Mg and Si are 496, 737 and 786 kJ mol^-1 respectively. The ionisation potential of Al will be closer to

Explain the following, give an appropriate reason.

The formation of \[\ce{F^-_{(g)}}\] from \[\ce{F_{(g)}}\] is exothermic while that of \[\ce{O^2-_{(g)}}\] from \[\ce{O_{(g)}}\] is endothermic.