Iron, cobalt, and nickel share similar properties and are grouped together in what is known as the iron triad due to their similar chemical and physical characteristics. Each of these metals is quite active, which means they readily react with other substances, particularly acids.
When these metals react with acids, they displace hydrogen from the acids, releasing hydrogen gas. In these reactions, the metals typically form +2 ions (cations with a +2 charge). However, cobalt and iron can also form +3 ions, illustrating their ability to participate in various oxidation states.
This versatility in oxidation states allows iron, cobalt, and nickel to take part in numerous chemical reactions and processes, making them essential in metallurgy and industrial applications. Their similar properties make them important not just individually, but also collectively in the field of materials science.