Question

1) does basicity of metal oxides increase along a group in the periodic table?
2) does basicity of metal oxides decrease along a period in the periodic table?

Answer 1

1) Basicity of the metal oxides increase as we go down the group. As the size of the metal atom increases the bond between the metal and the hydroxide ion becomes weak and OH ions are given up easily increasing the basicity.
2) Basicity of the oxides decreases across a period due to the small size of the elements which makes the bond between metal and hydroxide stronger.