Intoduction Indium is non alkali metal. It looks like silver, it is  the softest metal . It is a chemical element whose atomic number is 49 and symbolized as In. Indium is the post-transition metal that makes up 0.21 parts per million of the Earth's crust. It has a melting point lower than lithium and tin but higher than sodium and gallium. Indium is so soft that one can easily cut this...