The d-and f-Block Elements — Chemistry STD 12 Science — Question

→ Iron and steels. construction materials. are the most important
→ Their production is based on the reduction of iron oxides, the removal of impurities and the addition of carbon and alloying metals such as Cr, Mn and Ni.
→ Some compounds are manufactured for special purposes such as TiO for the pigment industry and MnO₂ for use in dry battery cells.
→ The battery industry also requires Zn and Ni/Cd.
→ UK 'copper' coins are copper-coated steel. The 'silver' UK coins are a Cu/Ni alloy. Many of the metals and/or their compounds are essential catalysts in the chemical industry.
→ V₂O₅ catalyses the oxidation of SO₂ in the manufacture of sulphuric acid.
→ TiCl₄ with Al(CH₃)₃ forms the basis of the Ziegler catalysts used to manufacture polyethylene (polythene).
→ Iron catalysts are used in the Haber process for the production of ammonia from N₂/H₂ mixtures. Nickel catalysts enable the hydrogenation of fats to proceed.
→ In the Wacker process the oxidation of ethyne to ethanal is catalysed by PdCl₂. Nickel complexes are useful in the polymerisation of alkynes and other organic compounds such as benzene. The photographic industry relies on the special light- sensitive properties of AgBr.