Study the following observations and name the anions present in each of the reactions. (a) When a crystalline solid 'P' is warmed with concentrated H2SO4 and copper turnings a reddish brown gas is released. (b) When few drops of dilute sulphuric acid is added to Salt 'R' and heated, a colourless gas is released which turns moist lead acetate paper silvery black. (c) When few drops of barium nitrate solution is added to the salt solution 'Q', a white precipitate is formed which is insoluble in HCl.

Rotten egg smell is due to the liberation of: (a) HCl gas (b) H₂S gas (c) Cl₂ gas (d) SO₂ gas

Fill in the blanks with the choices given in the brackets: (a) Metals are good ............... [oxidizing agents /reducing agents] (b) Non-polar covalent compounds are ............... [good / bad] conductors of heat and electricity. (c) Higher the pH value of a solution, the more is ............... [acidic / alkaline] it is. (d) ............... [Silver chloride / Lead chloride] is a white precipitate that is soluble in excess of Ammonium hydroxide solution. (e) Conversion of ethene to ethane is an example of ............... . [hydration / hydrogenation]

State one relevant observation for each of the following: (a) To the copper nitrate solution, initially few drops of sodium hydroxide solution is added and then added in excess. (b) Burning of ammonia in excess of oxygen. (c) Dry ammonia gas is passed over heated PbO.

Identify the cation in each of the following cases: (a) Ammonium hydroxide solution when added to Solution B gives a white precipitate which does not dissolve in excess of ammonium hydroxide solution. (b) Sodium hydroxide solution when added to Solution C gives a white precipitate which is insoluble in excess of sodium hydroxide solution.

Give one significant observation when: (a) Barium chloride solution is added to zinc sulphate solution. (b) Lead nitrate is heated strongly. (c) Chlorine gas is passed through moist starch iodide paper.

Identify only the anion present in the following compound: (a) The compound on heating produces a colourless, odourless gas which turns lime water milky and has no effect on acidified potassium dichromate solution. (b) The solution of the compound which on treating with concentrated sulphuric acid and freshly prepared ferrous sulphate solution produces a brown ring.

Rita was given an unknown salt for identification. She prepared a solution of the salt and divided it into two parts. To the first part of the salt solution, she added a few drops of ammonium hydroxide and obtained a reddish-brown precipitate. To the second part of the salt solution, she added a few drops of silver nitrate solution and obtained a white precipitate. Name: (a) the cation present and (b) the anion present in the salt given for identification.

Alex was given a solution of an unknown salt Y for analysis. He performed the following tests and recorded his observations: To a part of the solution Y, he added silver nitrate solution and obtained a white precipitate which was soluble in ammonium hydroxide solution. To the remaining solution he added a few drops of sodium hydroxide solution and obtained a pale blue precipitate. Based on the observations made by Alex, identify: (a) the anion and (b) the cation present in salt Y.

Complete the following sentences by choosing the correct option from the brackets: (a) The oxide that dissolves in caustic potash (KOH) is ............... . [ZnO / CuO] (b) The reaction that takes place at the anode during the electrolysis of molten lead bromide is ............... . [2Br − 2e− ⟶ 2Br− / 2Br− − 2e− ⟶ Br2] (c) The volume occupied by 8 grams of oxygen gas at STP is ............... litres. [5.6 / 8.96] [Atomic weight of O = 16] (d) ............... does not give hydrogen gas when it reacts with cold and very dilute nitric acid. [Cu / Mn] (e) ............... is a polar covalent compound. [HCl / CCl4]

Identify the following terms / compounds: (a) A compound which reacts with water to give acetylene gas. (b) The gas evolved when sodium propanoate is heated with soda lime. (c) A reddish-brown precipitate formed when ferric chloride solution reacts with an alkali. (d) A pair of electrons present in an atom which is not shared with any other atom during bond formation. (e) The relative molecular mass of a substance expressed in grams.

Differentiate between the following pairs of compounds using the reagent given in the bracket: (a) Ammonium chloride and Sodium chloride (using an alkali) (b) Zinc Nitrate solution and Calcium Nitrate solution (using excess sodium hydroxide solution)