Which of the following metals exist in their native state in nature?

(i) Cu

(ii) Au

(iii) Zn

(iv)Ag

An element A is soft and can be cut with a knife. This is very reactive to air and cannot be kept open in air. It reacts vigorously with water. Identify the element from the following:

Which one of the following properties are not generally exhibited by ionic compounds?

Metals are refined by using different methods. Which of the following metals are refined by electrolytic refining?

(i) Au (ii) Cu

(iii) Na (iv) K

Silver articles become black on prolonged exposure to air. This is due to the formation of: