Question

which metals are called class a elements or hard acid and why?

Answer 1

Class A metals are metals that form hard acids. Hard acids are acids with relatively ionic bonds. These metals, such as iron, aluminium, titanium, sodium, calcium and the lanthanides, would rather bond with fluorine than iodine. They form stable products with hard bases, which are bases with ionic bonds.

Answer 2

metal a ....such as ionic bond