An aqueous solution of a given salt was made alkaline with solid NH4CI and NH4OH solution. H2S gas was then passed through the test tube. A black ppt. appeared. Which of the following conclusions is most appropriate about the ppt?

Statement-I: The gas liberated on warming a salt with dil H2SO4, turns a piece of paper dipped in lead acetate into black, it is a confirmatory test for sulphide ion.Statement-II: In statement-I the colour of paper turns black because of formation of lead sulphite. In the light of the above statements, choose the most appropriate answer from the options given below:

Aqueous solution of which of the following compounds is alkaline in nature? Only one correct answerA.NH4ClB.CH3COONaC.H2CO3D.Na2SO4

A compound P is heated in a test tube with sodium hydroxide solution. A red litmuspaper held at the mouth of the test tube turns blue.Which of the following could compound P be?(a) zinc sulphate(b) copper sulphate(c) ferrous sulphate(d) ammonium sulphate

Take about 1g solid NaCl in a clean anddry test tube and set up the apparatus asshown in Fig. 2.4.n Add some concentrated sulphuric acid tothe test tube.n What do you observe? Is there a gas comingout of the delivery tube?n Test the gas evolved successively with dryand wet blue litmus paper.n In which case does the litmus paper changecolour?n On the basis of the above Activity, what doyou infer about the acidic character of:(i) dry HCl gas(ii) HCl solution?

Take about 1g solid NaCl in a clean anddry test tube and set up the apparatus asshown in Fig. 2.4.n Add some concentrated sulphuric acid tothe test tube.n What do you observe? Is there a gas comingout of the delivery tube?