Question

For the series of elements X, Y, and Z all in the same period (row), arrange the elements in order of decreasing first ionization energy. X=105, Y= 198, Z=266

Answer 1

Answer) Ionization energy is defined as minimum amount of energy required to remove an electron fro its outer most shell.

The general trend for ioization energy is as follow:

• Along Period- ionization energy increases moving from left to right as atomic radius decreases so the force of attraction between nucleus and electron increases and hence, more energy is required to remove an outer most electron.
• Along Row- ionization energy decreases moving from top to bottom as atomic radius increases so the force of attraction between nucleus and electron decreases and hence, less energy is required to remove an outer most electron.
• In a period moving from left to right the order is X, Y, Z (ionization energy increases from X to Z)
• In a period moving from right to left the order is Z, Y, X (ionization energy decreases from Z to X)