Answer to Question #163592 in General Chemistry for John

Question

 Research and tabulate values of first ionisation energy for the elements in groups 1 and 2 of the periodic table.

Plot graphs of first ionisation energy of the elements of groups 1 and 2 on the same axis.

Answer 1

Ionisation energy is that energy which is required to remove the electron from atom valence shell.

As the size of atom increases ionisation energy decreases.

we know that as we go from top to down in the graph size of atom increase and in period from left to right size decreases and ionisation energy increases.

Order is Fr<Cs<Rb<K<Na<Li

2^nd group=Ba<Sr<Ca<Mg<Be

Group 1. Ionization energy from highest to lowest

1. lithium Li 520
2. sodium Na 496
3. potassium K 419
4. rubidium Rb 403
5. cesium Cs 376
6. francium Fr 393

Group 2 ionization energy

1. beryllium Be 900
2. magnesium Mg 738
3. calcium Ca 590
4. strontium Sr 550
5. barium Ba 503