Modern inorganic chemistry

376 THE TRANSITION ELEMENTS one electron required (and also giving the vanadium a formal oxidation state of — 1). TESTS FOR VANA ...

THE TRANSITION ELEMENTS 377 therefore only found in combination with oxygen and fluorine. Of the lower oxidation states, the + 3 ...

378 THE TRANSITION ELEMENTS THECHROMATES(Vl) The chromates of the alkali metals and of magnesium and calcium are soluble in wate ...

THE TRANSITION ELEMENTS 379 + + 6e~ ^2Cr^3 + (aq) 4- 21H 2 O: E^= + 133V A standard solution of potassium dichromate can be made ...

380 THE TRANSITION ELEMENTS Addition of hydrogen peroxide to a solution of a dichromate yields the blue colour of 'peroxochromic ...

THE TRANSITION ELEMENTS 381 2+ 34- OH 2 The compounds also illustrate the very great tendency of triposi- tive chromium to form ...

382 THE TRANSITION ELEMENTS [2Cr(H 2 0) 6 ]3+ + 20H- =2 OH H,0 (H 2 0) 4 Cr OH H,O (H 2 O) 4 Cr' OH / x. (H 2 O) 4 Cr X''x /Cr(H ...

""HE TRANSITION ELEMENTS 383 CHROMIUM(H) CHLORIDE, CrCl 2 This is prepared by passing dry hydrogen chloride over chromium, or hy ...

384 THE TRANSITION ELEMENTS TESTS FOR CHROMATES AND DICHROMATES(VI) Addition of lead(II) nitrate in ethanoic acid solution give ...

THE TRANSITION ELEMENTS 385 it differs from the preceding transition metals in having a very stable 4- 2 oxidation state, corres ...

386 THE TRANSITION ELEMENTS oxidation of manganese(IV), by fusion of MnO 2 with potassium hydroxide, the usual method. This fusi ...

THE TRANSITION ELEMENTS 387 jn concentrated alkali, manganese(VI) is more stable than mangan ese(VII) and the following reaction ...

388 THE TRANSITION ELEMENTS This ion is derived from manganese(IV) chloride, MnCl 4 , but the latter has not been isolated. The ...

THE TRANSITION ELEMENTS 389 the hydrated Mn3+ ion, which (as expected for a tripositive cation), is strongly acidic. The complex ...

390 THE TRANSITION ELEMENTS The oxide MnO is obtained by heating the carbonate MnCO 3. Oxidation of manganese(II) in aqueous aci ...

THE TRANSITION ELEMENTS 391 as a peroxodisulphate or lead* IV) oxide and concentrated nitric acid, the purple colour of the mang ...

392 THE TRANSITION ELEMENTS When iron is refined, the process is essentially one of melting the iron in presence of materials wh ...

THE TRANSITION ELEMENTS 393 reduces some cations to the metal (for example copper) in aqueous solution, giving iron(II). Iron ab ...

394 THE TRANSITION ELEMENTS resemblance to manganese(II), except that most iron(III) compounds show high paramagnetism, i.e. the ...

THE TRANSITION ELEMENTS 395 kFeO(OH)'. The a-form is used as a red pigment, as a metal polish ("jeweller's rouge') and as a cata ...