13622.06R 12 Many inorganic reactions involve the production of a gas or the formation of a precipitate. (a) A series of reactions occurs when a piece of solid barium is added to a solution containing copper(II) sulfate. Bubbles of hydrogen gas are formed in the solution. A white precipitate and a blue precipitate are both produced. (i) Write an equation for barium reacting with water in the solution. [1] (ii) Write ionic equations for the reactions which occur to produce both precipitates. Identify the white precipitate and the blue precipitate. [4] 13622.06R [Turn over (b) The following tests were carried out on solutions labelled A, B and C and the results recorded in the table. Solution Test A B C Add silver nitrate solution white precipitate yellow precipitate no change Add hydrochloric acid no effervescence no effervescence effervescence Add ammonia solution green precipitate which dissolved in excess ammonia solution to form a blue solution blue precipitate which dissolved in excess ammonia solution to form a yellow solution no observable change (i) Write the formulae for the following which are highlighted in bold in the table. White precipitate Gas which causes effervescence Green precipitate Yellow solution [4] (ii) Identify A and B. A B [2] (iii) C cannot be fully identified from the tests carried out. Suggest one possible identity for C and describe another test which could be carried out to identify it more fully. [2]