Metallurgy — Chemistry STD 10 — Question

(a) Hydrogen is burnt in a greenish-yellow gas A then another gas B is formed. The gas B gives dense white fumes with ammonia liquor. Name the gases A and B.
(b) Burning sodium is taken in the gas B, when it forms a salt C and another colourless gas D. The salt solution of C gives a curdy white precipitate with silver nitrate solution. The white precipitate is soluble in excess of ammonium hydroxide.
(i) Name the salt C and Name the gas D.
(ii) Write the chemical equations for the reaction between
(1) B and sodium, (2) C and silver nitrate, (3) white precipitate and ammonium hydroxide

Answer the following questions :
(i) The pH of a solution S is 10. What is nature of solution?
(ii) If the pH of solution S is to be increased, name the compound we should add to it.
(iii) Name kind of particles present in the solution of carbonic acid.
(iv) Name kind of particles present in the glucose solution.

(a) Draw the structure of a compound with three carbon atoms in the following cases :
(i) An alkane with carbon to carbon single bond.
(ii) An alcohol containing three carbon atoms.
(iii) An unsaturated hydrocarbon with a double bond between any two carbon atoms.
(b) Methane, methene, methanoic acid and methanol.
From the list of compounds given above name:
(i) A compound which is not possible.
(ii) A compound used to denaturing ethanol.

Explain the following:
(i) When bromine vapours are passed into ethyne solution in carbon tetrachloride.
(ii) When a gaseous product obtained by the dehydration of alcohol is passed through bromine water.
(iii) Addition of ethyl alcohol to acetic acid in the presence of concentrated sulphuric acid.
(iv) A piece of sodium metal is put into ethanol at room temperature.

A metal article is to be electroplated with silver. The electrolyte selected is sodium argentocyanide.
(i) What kind of salt is sodium argentocyanide?
(ii) Why is it preferred to silver nitrate as an electrolyte?
(iii) State one condition to ensure that the deposit is smooth, firm and long lasting.
(iv) Write the reaction taking place at the cathode and anode.

A solution M turns blue litmus red while another solution N turns red litmus blue. In the above context answer the following questions :
(i) What do M and N must contain?
(ii) When M and N are mixed together, name one of the product formed.
(iii) When M and N are mixed together, name the other product formed.
(iv) If a piece of magnesium was put into a solution M, name the gas evolved.

An ionic compound is XBr₂. Answer the following questions on XBr₂ :
(i) Name the physical state of the ionic compound XBr₂.
(ii) What do you think about melting point of XBr₂?
(iii) What do you think about density of XBr₂ as compared to water?
(iv) Name the forces acting between the ions of XBr₂.

Bauxite is the chief ore of aluminium. The ore is first purified and then aluminium metal is extracted by electrolyic reduction.
(i) Write three balanced equations for the purification of ore by Hall's process.
(ii) Name the chemical used for dissolving pure aluminium oxide. In which state the chemical is used?
(iii) Write equations for the reactions taking place at the anode in a electrolytic tank.

Name the following:
(i) Second member of alkene series., (ii) First member of alkane series., (iii) Third member of aldehyde series., (iv) Second member of carboxylic acid.

Give balanced chemical equation for the following :
(i) Action of dilute hydrochloric acid on sodium sulphide.
(ii) Action of hydrochloric acid on sodium bicarbonate.
(iii) Action of dilute hydrochloric acid and magnesium sulphite.
(iv) Action of dilute hydrochloric acid on iron.