Hydrochloric add

By refluxing 54 and thioformamide for 16 hr m aqueous acetone solution, the expected compound 55 was obtained (Scheme 25). 55 in acetic medium, after treatment with hydrochloric add and zinc, gives 2-(4-thiazolyl)benziinida2ole derivatives 56 (554, 593). 

Hydrochloric add (HCI) Chemical manufactu well activation re, chlorine, food and rubber production, metal cleaning, petroleum... 

Hydrochloric add Floor and furniture polishes Vehicle exhausts Electric stencil cutting machines... 

Hempel fractionating column, 137 Hofmann s bottles 30 Hot-water funnel, 53 Hydrazobenzene, 146 Hydriodic acid, 113 Hydrobenzamide, 196 Hydrobromic acid, 140 Hydrochloric add gas, 93 Hydrocinnamic acid, 204 Hydrogen, qualitative determination, r quantitative, ... 

What is the volume of0.885 M hydrochloric add required to react with... 

Consider aqueous solutions of potassium hydroxide, potassium formate (KCHO2), hydrochloric add, and hypochlorous acid. 

The nitrate ion of the nitric acid acts as the oxidizing agent. The function of the hydrochloric add is to furnish Cl ions to form the very stable complex ion Audi. ... 

It may be purified by recrystallization from hot hydrochloric add, as recommended in Org. Syn. 3, 87, but on account of the difficulty of filtration this procedure is satisfactory on a small scale only. It is preferably distilled in 200-g. lots from a 500-cc. Claisen flask under 10-15 mm. pressure, b.p. 160-165V12 mm. It is important that no air inlet be used to prevent bumping, since under these conditions it partly sublimes and causes trouble by stopping up the connections. A filter or distilling flask is used as a receiver and only a short but wide bore (10 mm.) air condenser is necessary. This product is pale yellow and melts at 95-96°. The yield from 200 g. of crude product is 180-185 g-... 

Solutions of cerium(IV) sulphate in dilute sulphuric add are stable even at boiling temperatures. Hydrochloric add solutions of the salt are unstable because of reduction to cerium(III) by the add with the simultaneous liberation of chlorine ... 

This reaction takes place quite rapidly on boiling, and hence hydrochloric add cannot be used in oxidations which necessitate boiling with excess of cerium(lV) sulphate in add solution sulphuric add must be used in such oxidations. However, direct titration with cerium(IV) sulphate in a dilute hydrochloric add medium, e.g. for iron(II) may be accurately performed at room temperature, and in this respect cerium(IV) sulphate is superior to potassium permanganate [cf. (2) above]. The presence of hydrofluoric add is harmful, since fluoride ion forms a stable complex with Ce(lV) and decolorises the yellow solution. 

Procedure. Wdgh out accurately about 2.5g of finely powdered arsenic(III) oxide, transfer to a 500 mL beaker, and dissolve it in a concentrated solution of sodium hydroxide, prepared from 2g of iron-free sodium hydroxide and 20 mL of water. Dilute to about 200 mL, and neutralise the solution with 1M hydrochloric add, using a pH meter. When the solution is faintly add transfer the contents of the beaker quantitatively to a 500 mL graduated flask, add 2 g of pure sodium hydrogencarbonate, and, when all the salt has dissolved, dilute to the mark and shake well. 

After all the stannic chloride has been added, the cooling bath is removed and the mixture stirred for one hour longer. The addition product is hydrolyzed by the slow addition of a mixture of 90 cc. of water and 10 cc. of concentrated hydrochloric add. The yellow benzene layer is separated, washed with 25 cc. of water, and dried over 5-10 g. of anhydrous calcium chloride. Benzene and unchanged thiophene (Note 1) are distilled through a short fractionating column (using an oil... 

Drushel and Sommers96 also used zinc/hydrochloric add and Andreae97 chromium(II) chloride for reduction of sulphoxides. 

Aniline, 4,4 -azodi-, 40,18 Aniline, reaction with hexachlotoace-tone to form a, ,a-trichloro-acetanilide, 40, 103 reaction with maleic anhydride, 41,94 Anisoin, reduction to deoxyanisoin by tin and hydrochloric add, 40, 16... 

Hydrochloric Add Vapor-Sodium Nitrite/Hydrochloric Add-Amidosulfonic Add-N>(l-Naphthyl)-ethylenediamine... 

Note It is possible to differentiate amino acids by color on the basis of the markedly different shades produced [2, 3]. Proline and hydroxyproline, that only react weakly with ninhydrin, also yield pink-red colored derivatives [2]. Ergot alkaloids and LSD are detected by spraying with 10% hydrochloric add and then heating to 110°C for 20 min after they have been treated with the reagent [9]. Ergot alkaloids and LSD yield red to purple zones when treated in this manner other alkaloids, e.g. reserpine, emetine, quinine, strychnine, pilocarpine, atropine, scopolamine, cocaine and opium alkaloids, do not give a reaction [9]. 

Dipping solution Dissolve 200 mg sulfanilic acid and 600 mg N-(l-naphthyl)-ethylenediamine dihydrochloride in a mixture of 20 ml hydrochloric add (32%) and 10 ml water and make up to 200 ml with ethanol (1). 

Hydrochloric Add Vapor —Sodium Nitrite/Hydrochloric Acid—Amido-... 

Nitmus fumes Nitrous fumes can be generated in one trough of a twin-trough chamber by mixing a solution of 1 g sodium nitrite in 5 ml water with 5 ml fuming hydrochloric add. 

---