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

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

(i) Cu

(ii) Au

(iii) Zn

(iv)Ag

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

Galvanisation is a method of protecting iron from rusting by coating with a thin layer of:

Write true or false for the following statements:

Non-metals react with acids to give a salt and hydrogen gas.