结果1 题目18 Which substance causes the brown colour of aqueous bromine to disappear?A AB HH HH H C - C =C H-C→C→ C H C一C-O -H HH HH CD HH HO1H -C一C CC O -H/H HH n 相关知识点: 试题来源: 解析 A 反馈 收藏 ...
(e) A student added aqueous bromine to alkene C.C HCH2CH HH Describe the colour change seen and draw the structure of the product. Show all of the atoms and all of the bonds.colour change from... to...…structure(f) Two different alcohols can be produced from alkene B by an addit...
Elemental bromine is very reactive and thus does not occur free in nature, but in colourless soluble crystalline mineral halide salts, analogous to table salt. Čisti brom se ne nalazi u prirodi, već uglavnom u vidu bezbojnih, rastvorljivih kristalnih halidnih mineralih soli, analog...
1 - Phenyl - 3 - (6 - methylbenzthiazolylamino) - 5 - pyrazolone is prepared by refluxing together 1-phenyl-3-amino-5-pyrazolone, p - tolyl isothiocyanate, and pyridine, and adding a chloroform solution of bromine to the product. 1 - m - Chlorophenyl - 3 - phenylthiocarbamyl-amino-...
(Aloupi et al.2000; Maravelaki-Kalaitzaki and Kallithrakas-Kontos2003; Sotiropoulou2004; Coccato et al.2020); care must be taken, however, as a recent work (Aceto et al.2015) demonstrated that the sole evidence of bromine is not enough for an exclusive identification of Tyrian purple:...
The invention comprises pyrazolone colour couplers of the formula: wherein R is a phenyl group which may be substituted (e.g. by chlorine, bromine, nitro or cyano), R1 represents a halogen atom or an alkyl, alkoxy, nitro or acylamino group, and R2 represents hydroben or the same as R...
The compound enhances the whiteness of undyed materials and the brightness of dyed materials and it may be applied from a dilute aqueous solution. Many suitable compounds are specified and the following examples are given: (1) acetate silk is treated in a dilute aqueous solution of 3,31,5,51...
The invention comprises pyrazolone colour couplers of the formula: wherein R is a phenyl group which may be substituted (e.g. by chlorine, bromine, nitro or cyano), R1 represents a halogen atom or an alkyl, alkoxy, nitro or acylamino group, and R2 represents hydroben or the same as R...
a chlorine or bromine atom or a sulphonic or carboxylic acid group, which does not inhibit dye-coupling reactions, and which is generally split off during such reactions. Condensation may be effected in aqueous or non-aqueous media, e.g. in ether, acetone, acetic acid or dioxane, and a ...
(2) - amino] - 5 - pyrazolone is prepared by refluxing together 1-phenyl-3-amino-5-pyrazolone, phenyl isothiocyanate, and pyridine, acidifying, adding a chloroform solution of bromine to a chloroform solution of the precipitate, heating, dissolving in aqueous NaOH and heating, and precipitating...