Synthesis and Spectro-Kinetic Study of the Complexes of Pd+2 Ion with 2-(5-Bromo-2- pyridylazo)5diethylaminophenol Reagent in Ethanol – Water Solutions

The complexes of Pd+2 ion with 2-(5-bromo-2-pyridylazo)-5-dieıhyl aminophenol (BPADAP) were studied kinetically and spectrophotometrically in aqueous ethanolic solutions. The reagent forms 1:1, 2:1 square planer and 1:1 bridged shape binuclear complexes with Pd+2 ion. All these complexes (violet colour) absorb light in the same region at 540, 575 and 618nm. The band at 618 nm seems to be specific for complexes of Pd+2ion with BPADAP. The rate constants of the growth in 93% H2O + 7% ethanol of 1:1 and 2:1 complexes at 575 and 618 nm were followed the first order kinetics and are quite of the same values , 0.495 and 0.463 min- 1 respectively. The rate constants of the decay of 2:1 complex at 618 and 575 nm were followed the first order kinetics; their values are 0.075 and 0.065 min-1 respectively which are slower than the rate of the decay of 1:1 complex. Whereas, the rate constants of the growth and decay of 1:1 bridged binuclear complex also followed the first order kinetics but they are much slower than those of 1:1 and 2:1 complexes: the values of the growth are 025min-1at 575 nm , and 0.16 min-1 at 618 nm. And the values of the decay are 0.0476 min-1 at 575 nm and 0.008min-1 at 61 8 nm. It was found that BPADAP can identify and detect in ethanol at 575 and 618 nm less than one microgram up to more than seven micrograms of Pd+2 ion . The interference of UO2+2, Th+4, Pb+2 , Cd+2,Bi+3, Hg+2 and Zn+ 2 in the detection of Pd+2 ion at 575 nm ranges between (25.3 - 67)%. Whereas, the interference of these ions with the detection at 618 nm is only between (2.3 -3.9) %, so it is reasonable to suggest that BPADAP is a specific reagent for Pd+2 ion at 618 nm

Pityriasis rosea-like adverse reaction to atenolol

A 56-year-old female patient was presented with diffuse, bright red to violet colour, scaly patches on trunk and extremities after using a hypertension drug, atenolol. The patient was diagnosed as pityriasis rosea-like adverse reaction to atenolol based on her history, dermatological examination and histopathological findings. To the best of our knowledge, this is the first reported case of pityriasis rosea-like adverse reaction to atenolol that is widely used in hypertension treatment.

Darstellung und Eigenschaften von trans-Dihalogeno-tetrakis(pyridin)osmium(II)-Komplexen / Preparation and Properties of trans-Dihalo-tetrakis(pyridine)osmium(II) Complexes

The reaction of fac-K2[OsX3l3] (X = Cl, Br) with pyridine and glycerin gives dark red crystals of trans-[OsClI(py)4] or trans-[OsBrI(py)4], soluble in organic solvents, and sublimable in vacuum at 300 or 320 °C. The structure is established by vibrational and mass spectra. With HX adducts of type trans-[OsXI(py)4]·2 HX are formed, soluble in water with violet colour.

Note on the pleochroism of Adamite

The mineral adamite (Zns(AsO4)2.Zn(OH)2), discovered by C. Friedel in 1866 on specimens from Chafiarcillo, Chile, has since been found at only two other localities, namely Cape Garonne in France and Laurion in Greece. At the original locality it would appear to be of rare occurrence, since in the literature mention is made of only two specimens.It was therefore of interest to find in the British Museum collection a good specimen of adamite from Chafiarcillo. This was found amongst the hornsilvers, and the associated adamite had been thought to be fluorite, which indeed, at first glance, with its violet colour and good cleavage, it closely resembles in appearance. The crystals are remarkable by reason of their very strong pleochroism, and as this feature of adamite has previously received no mention it has been thought worthy of placing on record.

On the proteid reaction of Adamkiewicz, with contributions to the chemistry of glyoxylic acid

In 1874 Adamkiewicz* described the now familiar reaction which results in the production of a violet colour when strong sulphuric acid is added to the solution of a proteid in glacial acetic acid. Adam­kiewicz did not apparently look upon the employment of the acetic acid as introducing anything beyond a certain modification of the action of sulphuric acid.

II.—A Chapter in the History of Meteorites

Tschermak examined two microscopic sections of the Ovifak rocks, and compared them with sections of the meteorites of Jonsac, Juvinas, Petersburg, and Stannern, which consist chiefly of augite and anorthite, with little or no nickel-iron; they form a class which G. Rose termed ‘eucritic.’ Both sections exhibit a crust, as meteorites possess; it is, however, so altered by oxidation, that it is not possible to determine whether it is the fused crust usually noticed on a meteorite. The crystals of felspar, which, according to Nauckhoff's analyses, must be regarded as anorthite, are fully developed; they penetrate the augite, iron, and magnetite, and must evidently have been formed before them. They are completely transparent, and have but few and large cavities, which are filled, partly with black granules, partly with a brown substance of irregular form; some traversing the length of the crystals are filled with a transparent glassy substance. The augite is of a light greenish-brown hue, traversed here and there by flaws; it fills gaps between the other constituents, as has been often observed in dolerites and diabases, and encloses individual black grains. In the section containing iron the colourless felspar encloses a black or brown substance running the length of the crystals, or dust-like fine black granules, or larger round transparent bodies of a violet colour, which may be the mineral Nauckhoff regards as spinel.

VI. Some experiments and observations on a new substance which becomes a violet coloured gas by heat

A new and a very curious substance has recently occupied the attention of chemists at Paris. This substance was accidentally discovered about two years ago by M. Courtois, a manufacturer of saltpetre at Paris. In his processes for procuring soda from the ashes of sea weeds, (cendres de vareck) he found the metallic vessels much corroded; and in searching for the cause of this effect, he made the discovery. The substance is procured from the ashes, after the extraction of the carbonate of soda, with great facility, and merely by the action of sulphuric acid:— when the acid is concentrated, so as to produce much heat, the substance appears as a vapour of a beautiful violet colour, which condenses in crystals having the colour and the lustre of plumbago.