Question

The first and second ionization energies (KJ mol${}^{-1}$) of three elements A, B, and C are given below.

	A	B	C
IE${}_1$	402	650	1140
IE${}_2$	2642	1060	2070

Identify the element which is likely to be an alkali-metal.

• A. A
• B. B
• C. C
• D. Can't be predicted

Answer 1

The correct option is A A

Large jumps in the successive molar ionization energies occur when removing an electron from a noble gas(complete electron shell) configuration. The greater difference is shown by element A so it can be noble gas non-metal. Thus A is the alkali metal.