Organic Chemistry — Chemistry STD 10 — Question

A compound 'X' consists of 4.8% of C and 95.2% of Br by mass. 
Name the type of chemical reaction by which X can be prepared from ethane.

State how would you prepare copper (II) oxide from
copper sulphate

On treating with concentrated sulphuric acid, this salt changes from blue to white.

Elements lose electrons to complete their octet.

Name the anion present in the following compound:
When a barium chloride solution is added to a solution of compound B, a white precipitate insoluble in dilute hydrochloric acid is formed.

Calculate the weight/mass of: an atom of hydrogen

Identify the anion present of the following compound:
When barium chloride solution is added to salt solution E a white precipitate insoluble in dilute hydrochloric acid is obtained

In order to obtain one tone of aluminium, the following inputs are required:
4 tones of bauxite, 150 Kg of sodium hydroxide and 600 Kg of graphite.
The aluminium compound in bauxite is aluminium oxide and the main impurity is iron (II) oxide. Aluminium is obtained by the electrolysis of aluminium oxide dissolved in cryolite.
In construction work, why is the alloy of aluminium, duralumin used rather than pure aluminium.

Select from the list given (a to e) one substances in each case which matches the description given in parts (i) to (v). (Note : Each substance is used only one in the answer)
(a) Nitroso Iron (II) Sulphate
(b) Iron (III) chloride
(c) Chromium sulphate
(d) Lead (II) chloride
(e) Sodium chloride
(i) A compound which is deliquescent
(ii) A compound which is insoluble in cold water, but soluble in hot water
(iii) The compound responsible for the brown ring during the brown ring test of nitrate iron
(iv) A compound whose aqueous solution is neutral in nature
(v) The compound which is responsible for the green colouration when sulphur dioxide is passed through acidified potassium dichromate solution.

Explain, why only all glass apparatus should be used for the preparation of nitric acid by heating concentrated sulphuric acid and potassium nitrate.