Choose the correct answer from the choices given – The brown ring test is used for detection of:

(A) CO₃^2-
(B) NO₃^1–
(C) SO₃^2-
(D) C1^1-

(i) State the special feature of the apparatus used in the laboratory preparation of nitric acid?

(ii) State why the temperature of the reaction mixture of HNO₃ is not allowed to rise above 200°C.

Name the gas produced when copper reacts with concentrated nitric acid.

State one observation for the following: Zinc nitrate crystals are strongly heated.