Fill in the blanks with the choices given in the bracket:

When sodium chloride is heated with concentrated sulphuric acid below 200°C, one of the products formed is …………… [sodium hydrogen sulphate / sodium sulphate / chlorine]

State one observation for the following:

A small piece of zinc is added to dilute hydrochloric acid.

Complete the following by selecting the correct option from the choices given.

(i) The indicator which does not change colour on passage of HCl gas is ………….. [methyl orange, moist blue litmus, phenolphthalein].

(ii) The acid which cannot act as an oxidizing agent is …………… [conc. H₂SO₄, conc. HNO₃, conc. HCl]

Hydrogen chloride gas is prepared in the laboratory using conc. H₂SO₄ and NaCl. Answer the questions that follow based on this reaction.

(i) Give the balanced chemical equation for the reaction with suitable condition[s] if any.

(ii) Why is concentrated sulphuric acid used instead of conc. nitric acid.

(iii) How is the gas collected.

(iv) Name the drying agent not used for drying the gas.