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ammonia contains one-seventh of its weight of iron : find its formulæ.

1034. What volume of hydrochloric acid gas at N.T.P. is required to convert 89 grammes of pure iron into ferrous chloride, and what volume of chlorine at N.T.P. would convert the latter into ferric chloride ?

1035. How is iron alum made? Calculate its percentage composition.

COBALT.

1036. How does cobalt occur in nature? How is the metal prepared, and what are its properties ?

1037. What is the colour when anhydrous of (a) cobalt chloride, (6) cobalt iodide ? What changes occur on the addition of water to each ?

1038. Give a short account of the ammonio-cobalt bases.

1039. What is the action on cobalt chloride : (a) of potassium nitrite, (b) of potassium cyanide ?

1040. By what reactions is cobalt usually recognised? How is it distinguished from nickel?

NICKEL,

a

1041. Give a short account of the metallurgy of nickel. What is its chief use in the arts ?

1042. Describe a chemical process for preparing nickel perfectly free froin cobalt.

1043. What is the composition of German silver ?

1044. Compare the properties of nickel and cobalt, and point out the chief differences between them.

1045. It has been suggested that nickel and cobalt are really different forms of the same element. Give reasons for and against this hypothesis.

1046. How may the native sulphides of nickel, cobalt and iron be distinguished from each other?

1047. How is nickel sulphate prepared, and how much of the metal would be required to prepare 798 grammes of the crystallised salt?

PLATINUM.

1048. How does platinum occur in nature, and how is the metal prepared (a) by Wollaston's process, (6) by the process of Deville and Debray ?

1049. Describe the apparatus of Deville and Debray for fusing platinum.

1050. Why are platinum vessels frequently employed by chemists ? Name substances which attack platinum.

1051. What are platinum black and spongy platinum ? How are they each prepared, and how do they differ from ordinary platinum?

1052. How is platinum tetrachloride prepared, and how may the metal be obtained from it ?

1053. Express by equations the action of ammonium chloride on platinum chloride, and of heat on the product.

1054. What is the action (if any) of each of the following bodies when heated with platinum ? (a) potash, (6) silica, (c) nitric acid, (d) carbon, (e) lead, (f) sodium carbonate, (g) phosphorus, (h) chlorine, (i) sulphur, 6) potassium bisulphate.

M

LEAD.

1055. What is the composition of the following lead compounds ? (a) massicot, (6) galena, (c) litharge, (d) cerussite, (e) red lead, (S) pyromorphite, (g) anglesite.

1056. Describe methods for the assay of lead ores, and also for estimating the quantity of silver in argentiferous galena.

1057. How does lead sulphide itself serve for the reduction of the ore, without the addition of reducing agents ? Give equations.

1058. Describe the processes for lead-smelting in (a) reverberatory furnaces, (6) in blast-furnaces, (c) in shallow hearths.

1059. What is "lead fume," and what arrangements are made to collect it?

1060. Describe fully Pattinson's process for the desilverisation of lead; also the subsequent process of cupellation to obtain the silver.

1061. How are lead pipes and sheet-lead made ? 1062. What is the action of water on lead? Whether

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