Boric-acid Sentence Examples
It forms slightly coloured small crystals possessing a strong disagreeable smell, and is rapidly decomposed by water with the formation of boric acid and sulphuretted hydrogen.
A pentasulphide B2S5 is prepared, in an impure condition, by heating a solution of sulphur in carbon bisulphide with boron iodide, and forms a white crystalline powder which decomposes under the influence of water into sulphur, sulphuretted hydrogen and boric acid.
Boron trioxide B203 is the only known oxide of boron; and may be prepared by heating amorphous boron in oxygen, or better, by strongly igniting boric acid.
The specific effect of boric acid in this respect was correctly ascertained by Stokes and Harcourt, but they mistook the effect of titanic acid.
It combines directly with ammonia to form the compound SiF 4 2NH,, and is absorbed by dry boric acid and by many metallic oxides.Advertisement
The soffioni contain a small quantity of boric acid (usually less than o 1%), together with a certain amount of ammoniacal vapours.
The operation is carried on through the entire series, until the liquor in the last basin contains about 2% of boric acid.
Artificial soffioni are sometimes prepared by boring through the rock until the fissures are reached, and the water so obtained is occasionally sufficiently impregnated with boric acid to be evaporated directly.
The residue is then heated in a current of superheated steam, in which the boric acid volatilizes and distils over.
Its action upon turmeric is characteristic; a turmeric paper moistened with a solution of boric acid turns brown, the colour becoming much darker as the paper dries; while the addition of sodium or potassium hydroxide turns it almost black.Advertisement
The supply of borax is, however, mainly derived from the boric acid of Tuscany, which is fused in a reverberatory furnace with half its weight of sodium carbonate, and the mass after cooling is extracted with warm water.
An alternative method is to dissolve sodium carbonate in lead-lined steamheated pans, and add the boric acid gradually; the solution then being concentrated until the borax crystallizes.
The boric acid being scarcely ionized gives only a very small quantity of hydrogen ions, whilst the base (sodium hydroxide) produced by the hydrolysis occasioned by the dilution of the solution, being a "strong base," is highly ionized and gives a comparatively large amount of hydroxyl ions.
The boron contained in solution in the salt lakes has very probably been supplied by hot springs and solfataras of volcanic origin, such as those which at the present day charge the waters of the lagoons in Tuscany with boric acid.
Raschig (Be y ., 1908, 4 1, p. 4 1 94) as a highly explosive colourless gas on acidifying a mixture of sodium azide and hypochlorite with acetic or boric acid.Advertisement
Another bait is 2 percent boric acid and 98 percent light corn syrup.
Kiihne (D.R.P. 147,871) described a process in which external heating is not necessary, a mixture of aluminium turnings, sulphur and boric acid being ignited by a hot iron rod, the resulting aluminium sulphide, formed as a by-product, being decomposed by water.
After fusion the mass solidifies to a transparent vitreous solid which dissolves readily in water to form boric acid (q.v.); it is exceedingly hygroscopic and even on standing in moist air becomes opaque through absorption of water and formation of boric acid.
Boron can be estimated by precipitation as potassium fluoborate, which is insoluble in a mixture of potassium acetate and alcohol, For this purpose only boric acid or its potassium salt must be present; and to ensure this, the borate can be distilled with sulphuric acid and methyl alcohol and the volatile ester absorbed in potash.
The chief source of boric acid for commercial purposes is the Maremma of Tuscany, an extensive and desolate tract of country over which jets of vapour and heated gases (soffioni) and springs of boiling water spurt out from chasms and fissures.Advertisement
One of the best ways to control roaches in your home is with old fashioned boric acid.
Further, some solutions contain ingredients that have been known to lead to cancer, such as sodium chloride or boric acid.
If cockroach allergen is causing asthma attacks, the roaches should be killed (using poison, traps, or boric acid rather than chemicals).