Even differences in hygroscopic properties--that is to say, in the degree of avidity with which a mineral takes up moisture from the atmosphere--may be made available for the purpose of effecting a commercially valuable separation.
Otherwise a desiccator must be employed; this is essentially a closed vessel in which a hygroscopic substance is placed together with the substance to be dried.
It is almost colourless and has a small coefficient of expansion; its hygroscopic properties, its viscous character, and its action on the skin, however, militate against its use.
Of the hygroscopic substances in common use, phosphoric anhydride, concentrated sulphuric acid, and dry potassium hydrate are almost equal in power; sodium hydrate and calcium chloride are not much behind.
The salts formed by the alkaloid with the acids are generally hygroscopic and uncrystallisable, but an exception is met with in the hydrobromide, which crystallises in stellate groups.
Water, when combined as hygroscopic water, does not lose its properties and does not form new substances.
From what has been said above, it is evident that the transference of moisture to gases and the absorption of hygroscopic moisture present great resemblance to, but still are not, chemical combinations with water.
By weighing a substance before and after drying, it is easy to determine the amount of hygroscopic water from the loss in weight.
The small [U] tube contains hygroscopic substances, and is weighed before the experiment: this is in order to know whether the hydrogen passing through still retains any moisture.
The curly or twisted character of the fibre is caused by the unequal contraction of the outer scales, and depends in a great measure upon the hygroscopic nature of the wool.
Wool is a much more hygroscopicfibre than cotton or any of the other vegetable fibres, usually it contains about 18 per cent.
The cover has also incidentally the effect of keeping damp and fumes from the clock and thus preserving it from rust, especially if a vessel with quicklime or some hygroscopic material be put in the case.
The proportion of carbon is comparatively low, usually not exceeding 70%, while the oxygen and hygroscopic water are much higher than in true coals.
Gum substitutes consisting entirely of some form of gelatin with water, like fish glue, are also somewhat hygroscopic when dried.
The hygroscopic nature of dextrins renders them unsuitable for foreign work, but when the quantity of starch is appreciable, better results are obtainable.
The hotter the tar, the more rapid the saturation; the high degree of heat expels the air and evaporates the hygroscopic fluid in the pores of the paper.
Bodies like "arabol" made up with water and containing gelatin are very hygroscopic when dry, although as sold they lose water on exposure to the air.
In addition to their texture or permeability to air, and to their conducting or non-contracting powers, fabrics also vary according to their hygroscopic qualities.
We may illustrate what we mean by the hygroscopic movements of plants: if the tissues on one side of an organ permit of rapid evaporation, they will dry quickly and contract, causing the part to bend to this side.
By warming its aqueous solution with an excess of silver oxide it is converted into tetramethylammonium hydroxide, N(CH3)4OH, which crystallizes in hygroscopic needles, and has a very alkaline reaction.
It is therefore possible to use them also to remove the moisture in the gas, if a material hygroscopic in nature is employed to charge them.
This should be true more particularly with puratylene, which contains a notable proportion of the very hygroscopic body calcium chloride.
Footnote 15: Some clays are highly hygroscopic and absorb moisture readily from the atmosphere.
Furthermore, the hygroscopic and soluble organic substances in admixture cannot extemporaneously be so prepared in sealed capsules as to be readily available under the practical requirements of prescribing and dispensing.
They arehygroscopic and the water mixtures undergo decomposition on standing.
The hygroscopic moisture of the product is lowered from 10-11 p.
The hygroscopic moisture under ordinary atmospheric conditions is 3.
The most important hygroscopicas well as thermoscopic influence of the forest is, no doubt, that which it exercises on the humidity of the air and the earth, and this climatic action it exerts partly as dead, partly as living matter.
Uchatius, in Austria, proposed a smokeless powder made from nitrated starch, but it was not adopted owing to its hygroscopic nature and also its tendency to detonate.
The moisture and hygroscopic test consists in weighing a sample, drying at 100 deg.
The claim is made: “The levulose of prunes, a constituent of Prunoids, is hygroscopic and thus when brought into contact with the saliva of the mouth or contents of the stomach, disintegrates and prompt medication is insured.
With this calorimeter it is desired to make studies regarding the moisture elimination, and consequently it is necessary to avoid the use of all material of a hygroscopic nature.
This moisture which goes into the cell walls hygroscopic moisture, and the property which the wood substance has of taking on hygroscopic moisture is termed hygroscopicity.
On the other hand, its more complex structure usually renders the hygroscopic moisture quite difficult to extract.
In general, however, the hygroscopic moisture necessary to saturate the cell walls is termed the "fibre saturation point.
Usually wood contains not onlyhygroscopic moisture but also more or less free water in the cell cavities.
In the latter, it is largely a matter of evaporated moisture, but wood is not only hygroscopic and attracts moisture from the air, but its physical behavior is very complex and renders the extraction of moisture a very complicated process.
This reasoning is not at all satisfactory, because rocksalt is very hygroscopic and becomes wet, even in unsaturated air, if the vapour pressure is greater than that of a saturated solution of salt at the temperature of the plate.
It is possible that the walls of Tyndall's tube may have become covered with a veryhygroscopic film from the powder of the calcium chloride which he was in the habit of introducing near one end.
They are largely beyond the power of the microscope, and some of them, indeed, appear to be of molecular size, consisting of molecules of hygroscopic gases, such as the oxides of sulphur and of nitrogen.
Bichromate and Sugar= are never used alone, but as an addition to heighten the sensitiveness and increase the hygroscopic properties of the gelatine or gum-chromate solutions.
These processes are all based upon the change in the hygroscopic properties of chromated gelatine brought about by the action of light, which renders the parts exposed insoluble.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "hygroscopic" in a variety of sentences. We hope that you will now be able to make sentences using this word.
