Mention one suitable laboratory procedure for
(i) removing carbon (IV) oxide from a sample of air
(ii) determining whether a given sample of water is pure or not;
(iii) concentrating a dilute solution of sodium chloride.
(b) Use the information provided in the table below to outline a suitable procedure for separating a mixture containing P, Q and R into its Components.
| Component | Solubility in tetrachloromethane | Solubility in water |
|
P Q R |
Insoluble Soluble Insoluble |
Insoluble Slightly soluble soluble |
(c)(i) Draw a labelled sketch to illustrate the collection of gases by upward displacement of air.
(ii) A gas S, with a rotten egg smell, was evolved when dilute hydrochloric acid was added to T which is a salt of iron (II). S decolorized acidified potassium tetraoxomanganate (VIl) solution and a yellow precipitate V was also obtained. Identify S, T and V.
(iii) State what would be observed on bubbling chlorine through a solution of potassium bromide.
Explanation
(a)(i) Pass/ bubble air through caustic soda (NaOH) or caustic potash (KOH) lime water.
(ii) Determine its boiling point/ freezing point.
(iii) Heat/warm/ boil to evaporate off some of the water.
(b) Add CCl\(_4\), Q dissolves. Filter off solution of Q add water to the residue, R dissolves. Then filter and obtain P as residue
(c)(i) Labelling of gas jar and delivery tube are the two major components.
(ii) S is H\(_2\)S; T is FeS; V is sulphur
(iii) Brown/Reddish brown coloration.