Methyl alcohol density

Technical formalin contains 8-10 per cent of methyl alcohol, so that it is not possible to use the table of densities (Note i of the preparation) for determining the formaldehyde content of the solutions. For example, a solution containing 37 per cent of formaldehyde and 10 per cent of methyl alcohol would have a density of 1.09 and correspond to 28 per cent of formaldehyde in pure water. In view of this, the recorded yield should probably be 64-66 per cent instead of 86-89 cent. 

Methyl alcohol. Methyl alcohol may be detected by the reactions indicated on p. 254. If the aqueous solution contains only methyl alcohol, or this with small quantities of acetone (for detection of acetone, see below, paragraph 3), the amount of this alcohol in 100 grams of the varnish may be deduced from the density of the distillate (see table, Vol. I, p. 40). If ethyl alcohol (detected as in paragraph 2) also is present, the methyl alcohol is determined either colorimetrically or by combustion (see p. 258). The amount thus found is deducted from the total alcohol determined from the density of the distillate by means of the ordinary tables for ethyl alcohol, the remainder being the amount of the latter alcohol.1... 

The densities of methyl and ethyl alcohols and of separate solutions of corresponding concentrations are very nearly equal, so that for approximate determinations the ethyl alcohol table may be used for methyl alcohol or for mixtures of the two. 

Methyl alcohol can be oxidised under certain conditions to formaldehyde with a yield of 80 per cent. Elbs and Brunner employed 160 grams of methyl alcohol and 75 grams of sulphuric acid per litre. A smooth platinum anode with a current density of 3 75 amps, per dm.2 gave good results at 30° C., whilst anodes of platinised platinum or lead peroxide gave a low yield of formaldehyde and much carbon dioxide. 

Ammonium chloride (NH4C1, density 1.52) is a white crystalline solid that decomposes at 350°C and sublimes at 520°C under controlled conditions. It is also known as sal ammoniac and is soluble in water and in aqueous solutions of ammonia it is slightly soluble in methyl alcohol. 

Methyl alcohol (methanol, wood alcohol, CH3OH boiling point 64.7°C, density 0.7866, flash point 110°C) is a colorless, mobile liquid with a mild characteristic odor (and narcotic properties) that is miscible in all proportions with water, ethyl alcohol, or ether. When ignited, methyl alcohol burns in air with a pale blue, transparent flame, producing water and carbon dioxide. The vapor forms an explosive mixture with air. The upper explosive limit is 36.5% and the lower limit is 6.0% by volume in air. 

While these experiments, which were carried out without giving a theoretical insight into the nature of the electrochemical reaction, yielded almost all the possible oxidation products in the oxidation of methyl alcohol, Elbs and Brunner 2 have discovered a method which gives 80% of the current yield in formaldehyde. This is exactly the substance which could not be proven present up to that time among the electrolytic oxidation products of methyl alcohol. Elbs and Brunner electrolyzed an aqueous solution of 160 g. methyl alcohol and 49 to 98 g. sulphuric acid in a litre. They employed a bright platinum anode in an earthenware cylinder, using a current density of 3.75 amp.1 and a temperature of 30°. Only traces of formic acid and carbonic acid and a little carbon monoxide, aside from the 80 per cent, of formaldehyde, were formed. Plating the platinum anode with platinum decreased the yield of formaldehyde at the expense of the carbon dioxide. With an anode of lead peroxide the carbon dioxide exceeded the aldehyde. 

The crystals are red in colour, of density 1 1 924, and isomorphous with their iron and nickel analogues. They melt at 96° to 98° C.,2 and effloresce upon exposure to air, losing one molecule of water. Practically insoluble in absolute ethyl alcohol,3 the crystals readily dissolve in methyl alcohol and in water, the solubility in the last-named solvent being as follows 4 ... 

Methanol (methyl alcohol). The commercial product is a clear, colourless liquid with a characteristic odour. It boils at 64 7°C and has a density of 0 79 gem"3. It is POISONOUS (causing blindness and ultimately death) and should therefore never be tasted. 

Methyl phenylarsinate, C6H5.AsO(OCH3)2, is a colourless liquid, B.pt. 188° C. at 95 mm., density 1-8946 at 23° C. it is readily decomposed by water to the acid and methyl alcohol. The ethyl ester boils at 168° to 170° C. at 16 mm., density 1-318 at 15 C. When treated with chlorine it yields phenylliydroxychloroarsinc, chloral, and hydrogen chloride. ... 

The acid may be derived from atoxyl in the following manner Commercial atoxyl (155 grams) is dissolved by gentle heating in 600 c.c. of water and 65 c.c. of hydrochloric acid (density 1-12) added. After several hours, the precipitate is filtered off and washed with cold water until free from hydrochloric acid, then washed with alcohol and ether and dried in the air. The yield is quantitative. The acid thus obtained is readily soluble in methyl alcohol, sparingly soluble in ethyl alcohol and acetic acid, insoluble in ether, acetone, chloroform, and benzene. It shows feebly basic properties, and when evaporated to dryness with hydrochloric acid forms a hydrochloride, whidi does not give a clear solution in water and may be precipitated from its solution by alcohols. ... 

Oxalyl - p - aminophenylarsinic acid, COaH.CO.NH-CgHgAsO (011)2. — mixture of 347 grams of sodium p-arsanilate and 378 grams of crystallised oxalic acid are heated at a temperature of 120° to 180° C. until the bulk of the water is driven off, the temperature then being slowly raised to 160° C., until the mass becomes pulverulent. After cooling, it is mixed with 3000 e.c. of water, 390 c.c. of hydrochloric acid (density 1 12) are added and the mixture stirred for thirty minutes. The crude product is dissolved in 700 c.c. of cold water and 200 c.c. of 7N sodium hydroxide, the filtered solution being treated with 890 c.c. of hydrochloric acid (density 1 12) to precipitate the oxalyl derivative. The latter is a white powder, unmelted at 860° C., soluble in hot water, alkali hydroxide and carbonate, insoluble in acids and sparingly soluble in methyl alcohol. 

A solution of 8-6 grams of 5-nitro-6-amino-j i-tolylarsinic add in 75 c.c. of water and 6 2 c.c. of lOAT sodium hydroxide solution is cooled to —1° C. and 20-4 grams of sodium hydrosulphite added in one oiJeration. When the reaction is complete the solution is filtered and 8-1 c.c. of hydrochloric acid (density 1 12) added. The arsinic acid separates and is recrystallised from water. It forms colourless needles, containing 1J to 2 mols. of water of crystallisation. It is soluble in methyl alcohol and acetic acid, sparingly soluble in ether, benzene, and petroleum. Its solution in dilute hydrochloric acid gives a chai acteristic deep violet coloration with a drop of dilute solution of potassium dichromate. 

A solution of 10 grams of stannous chloride in 40 c.c. of hydrochloric acid (density 1 -19) is treated with 1 c.c. of hydriodic acid (density 1-7) and the whole cooled in ice. The solution is well stirred, and 5 3 grams of 3-nitro-4-hydroxyphenylarsinic acid in 20 c.c. of methyl alcohol added dropwise. The precipitated arseno-compound is filtered off and washed with methyl alcohol. 

A solution containing 22 grams of y>aminophenylarsenoxidc and 18 15 grams of arsenic trichloride in 100 c.c. of methyl alcohol is slowly added to a well-coolestannous chloride in 200 c.c. of hydrochloric acid (density 1 19) and 200 c.c. of methyl alcohol. The product is brownish-yellow and cont ns 45 per cent, of arsenic. It is soluble in hot dilute hydrochloric acid and in moist pyridine, the acid solution yielding precipitates with dilute sulphuric acid and excess of sodium hydroxide. 

Methyl alcohol, CH3OH, with a density of 0.79 g/mL, can be used as fuel in race cars. Calculate the volume of air needed for the complete combustion of 51.0 mL CH3OH. 

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