Assertion : NaCl reacts with concentrated `H_2SO_4` to give colourless fumes with pungent smell. But on adding `MnO_2` the fumes become greenish yellow. Reason : `MnO_2` oxidises HCl to chlorine gas which is greenish yellow.

On addition of conc. H_2SO_4 to a chloride salt, colourless fumes are evolved but in case of iodide salt, violet fumes come out. This is because

The reactions of Cl_2 gas with cold-dilute and hot-concentrated NaOH in water give sodium salts of two (different) oxoacids of chlorine, P and Q, respectively. The Cl_2 gas reacts with SO_2 gas, in the presence of charcoal, to give a product R. R reacts with white phosphorus to give a compound S. On hydrolysis, S gives an oxoacid of phosphorus, T. Answer the following (11-12) questions: R, S and T, respectively, are

Give an example of a reaction in which H_2SO_4 behaves as : an oxidising agent.

A substance 'S' is used as a building material and is insoluble in water. When reacted with dil H_2SO_4 it produces a gas 'X' which turned lime water milky. When the liberated gas 'K' passed in excess, the milkiness disappeared. Write the name and chemical formula of S and its reactions will dil H2SO4, name the acid and base from which the substance 'S' is made.

Give an example of a reaction in which H_2 SO_4 behaves as an oxidising agent.

When conc. H_2SO_4 was added to an unknown salt present in a test tube, a brown gas (A) was evolved. The gas intensified when copper turnings were also added into this test tube. On cooling the gas A changed into a colourless gas (B). Write the equations for the reactions involved.

When conc. H_2SO_4 was added to an unknown salt present in a test tube, a brown gas (A) was evolved. The gas intensified when copper turnings were also added into this test tube. On cooling the gas A changed into a colourless gas (B). Identify the gases (A) and (B).

A water soluble compound 'X' of sodium on reacting with dil. H_2SO_4 released a colourless gas accompanied by brisk effervescence. When the gas was passed through water, the solution obtained turned blue litmus solution red. On bubling the gas through lime water, it initially became milky and the milkness disappeared when the gas was passed in excess. Identify the substance 'X' and write the chemical equation for the reactions involved.

each question constain STATEMENT-1(Assertion ) and STATEMENT - 2 (reason). examine the statement carefully and work the correct answer accoridng to the instructions given below : STATEMENT-1: When SnO_(2) is reacted with NaOH , then its sol particles are attracted towards cathode. STATEMENT-2: When SnO_(2) is reacted with NaOH, then it gives SnO_(3)^(2-) which is adsorbed by SnO_(2) , so it is negatively charged sol. if both the statement are TRUE and STATEMENT -2 is the correct explanation of STATEMENT - 1 , If both the statement TRUE are STATEMENT -2 is NOT the correct explanation of STATEMENT -1 , If STATEMENT -1 is TRUE and STATEMENT - 2 is FALSE , If STATEMENT -1 is FALSE and STATEMENT -2 is TRUE.