Blue-green

Ni(NH4)2(S04)2,6H20. Blue-green crystalline material formed from a solution of the components. Used in electroplating. 

Disulphur trioxide, S2O3. Blue -green solid S plus SO3. 

The O oxidation state is known in vanadium hexacarbonyl. V(CO)(,. a blue-green, sublimable solid. In the molecule VfCO), if each CO molecule is assumed to donate two electrons to the vanadium atom, the latter is still one electron short of the next noble gas configuration (krypton) the compound is therefore paramagnetic, and is easily reduced to form [VfCO, )]. giving it the... 

The anhydrous chloride is prepared by standard methods. It is readily soluble in water to give a blue-green solution from which the blue hydrated salt CuClj. 2H2O can be crystallised here, two water molecules replace two of the planar chlorine ligands in the structure given above. Addition of dilute hydrochloric acid to copper(II) hydroxide or carbonate also gives a blue-green solution of the chloride CuClj but addition of concentrated hydrochloric acid (or any source of chloride ion) produces a yellow solution due to formation of chloro-copper(ll) complexes (see below). 

When cobalt(II) chloride was dissolved in water, a pink solution A was formed. The addition of concentrated hydrochloric acid to A gave a blue solution B. If solution A was treated with concentrated ammonia solution a blue-green precipitate was formed upon addition of further ammonia solution followed by the passage of air through the mixture, an orange-red solution C was produced. 

Note that some of the metals frequently encountered in simple organic compounds give characteristic flame colorations Na, yellow K, lilac through blue glass Ca, brick-red Ba, apple-green Cu, bright blue-green. Ag and Pb, no characteristic flame. 

Secondary nitro compound dark blue or blue green colour due to nitro-iiitroso derivatives. The coloured compound is soluble in chloroform. 

In a more elaborate and specific synthesis, the terpenoid indole skeleton found in haplaindole G, which is isolated from a blue-green alga, was constructed by addition of a nucleophilic formyl equivalent to enone 6.5A. Cyelization and aromatization to the indole 6.6B followed Hg -catalysed unmasking of the aldehyde group[6]. 

Nickel sulfate NiS04 6H2O (pale blue) (green) ... 

Sulfates. Iron(II) sulfate heptahydrate [7782-63-0] FeSO forms blue-green monoclinic crystals that are very soluble in water and... 

The unstable pale blue-green bis(2,276, 2 -terpyridine)iron(3+) ion [47779-99-7], [Fe(terpy)2], has been obtained by oxidation of [Fe(terpy)2]. It is very unstable with respect to reduction by solvent and ligand dissociation. The perchlorate salt [2153642-5] has been reported. 

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