Get premium membership and access revision papers with marking schemes, video lessons and live classes.
(a) Give the name of each of the processes described below which takes place when salts are exposed to air for sometime.
(i) Anhydrous copper sulphate become wet.
(ii) Magnesium chloride forms an aqueous solution .
(iii) Fresh crystals of sodium carbonate, #Na_2CO_3#.#10H_2O#, become covered with white powder of formula,# Na_2CO_3.H_2O#
(b) Write the formula of the complex ion formed in each of the reactions described below.
(i) Zinc metal dissolves in hot alkaline solution
(ii) Copper hydroxide dissolves in excess ammonia solution
(c) A hydrated salt has the following composition by mass.
Iron 20.1%, oxygen 23.0%, sulphur 11.5%, water 45.3%. Its relative formula mass is 278.
(i) Determine the formula of the
hydrated salt. (Fe=56, S=32, O=16,H=1)
(ii) 6.95g of the hydrated salt were dissolved in distilled water and the total volume made to #250cm^3# of the solution. Calculate the
concentration of the salt solution in moles per litre.