The organic matter of the urine prevents the precipitation of cupric hydrate on the addition of the alkali.
Pavy's ammonia cupric process distances all compeers for ease of application and delicacy of end-reaction, combined with considerable accuracy.
Trommer's test consists in adding enough cupricsulphate to color green, then excess of alkali, and boiling.
This is based upon the fact that when potassic iodide in excess is added to a strong solution of a cupric salt in a faintly acid solution, cuprous iodide is formed and an equivalent of iodine liberated.
The finishing point is reached as soon as the solution becomes turbid from precipitated cupric hydrate.
They are easily and completely converted into cupric by oxidising agents.
Cupric compounds are generally green or blue, and are soluble in ammonia, forming deep blue solutions.
The analysis was then reported as follows:-- Cupricoxide 70.
Taking 2 grams of it for each determination, what weight of CO{2} will be got on burning the residue from solution in ammonium cupric chloride, and what from the residue after solution in hydrochloric acid?
Required the formula of a mineral which gave the following figures on analysis:-- Cupric oxide (CuO) 10.
Cupric salts are easily made by dissolving cupric oxide in acids, or, when insoluble, by precipitation.
The cupric salts are much the more common of the two, since the cuprous salts pass readily into cupric by oxidation.
Contrast the action of heat oncupric nitrate and mercuric nitrate.
Copper, like iron, forms two series of compounds: in the cuprous compounds it is univalent; in the cupric it is divalent.
Next boil it along with cupric oxide, which precipitates only the uranic and ferric oxides.
In this process we may substitute plumbic oxide for the cupric oxide, and succeed equally well.
The alcoholic solution being now evaporated to dryness, the residue is to be digested in water of ammonia, when the cupric oxide will be dissolved, and the oxide of iron will remain.
In certain plants the application of cupric solutions as sprays causes a slight increase in the quantity of sugar present in the matured fruits.
By injecting small quantities of cupric salts into the branches of currants an acceleration of the maturation of the fruits was caused, identical with that obtained by the application of Bordeaux mixture to the leaves.
This metal now converts the ferricyanate in the ferro compound, which, by another action, forms bothcupric and uranic ferrocyanate.
Under the luminous agency the uranic nitrate is first reduced, then the uranous oxide acts on the cupric nitrate, forming cupric oxide, which is finally reduced to the metallic state.
Acetylene reacts at ordinary temperatures with an ammoniacal solution of any cupric salt, forming a black cupric compound of uncertain constitution which explodes between 50° and 70° C.
At more elevated temperatures other cupric compounds are produced which also give evidence of polymerisation.
Copper is a metal which yields two series of compounds, cuprous and cupric salts, the latter of which contain half the quantity of metal per unit of acid constituent that is found in the former.
The latter is converted into carbonic acid by passing the products of combustion through a tube F, containing cupric oxide heated in a furnace.
The cupric oxide oxidises this CO into CO{2}, forming metallic copper.
Copper sulphate is readily soluble in water, but insoluble in alcohol; it dissolves in hydrochloric acid with a considerable fall in temperature, cupric chloride being formed.
The bulk of the copper is thus transformed into cupric chloride, little cuprous chloride being obtained.
Copper dioxide, CuO2H2O, is obtained as a yellowish-brown powder, by treating cupric hydrate with hydrogen peroxide.
Cupric nitrate, Cu(NO3)2, is obtained by dissolving the metal or oxide in nitric acid.
The precipitation of the copper from the solution, in which it is present as sulphate, or as cuprous and cupric chlorides, is generally effected by metallic iron.
Cupric chloride, CuCl2, is obtained by burning copper in an excess of chlorine, or by heating the hydrated chloride, obtained by dissolving the metal or cupric oxide in an excess of hydrochloric acid.
Copper arsenate is similar to cupric phosphate, and the resemblance is to be observed in the naturally occurring copper arsenates, which are generally isomorphous with the corresponding phosphates.
Cupric phosphate, Cu3(PO4)2, may be obtained by precipitating a copper solution with sodium phosphate.
The first of these was no doubt finely divided copper metal; the second, third, and fourth were probably all cupric oxide.
Judging from the heat effect produced on dissolving cupric chloride in a large bulk of water, we should predict that the solubility of that salt would diminish with rise of temperature; as a matter of fact, it increases.
The cupric reduction falls in greater ratio to the original (unfermented) than the furfural.
The numbers for cupric reduction were in excess of those obtained with the hexoses.
The products were digested with dilute hydrochloric acid six hours at 100°, and the cupric reduction of the soluble products determined and calculated to dextrose.
The yields of glucose, calculated from the cupric reduction, were as follows:-- Boletus edulis 65.
In the early stages also the permanent tissue yields an extract with relatively low cupric reduction, showing that the carbohydrates are dissolved by the acid in a more complex molecular condition.
Cuprammonium solution was prepared by dissolving the precipitated cupric hydrate in 24 p.
The products were oxycelluloses, with a cupric reduction equal to that of an oxycellulose directly prepared by the action of HClO{3}.
Both potassium bromate and cupric salts in solution will liberate iodine from an iodide, which is then titrated with the thiosulphate solution.
What weight of metallic copper will be deposited from a cupric salt solution by a current of 1.
The best of the many solutions which have been proposed in years gone by is very dilute cupric nitrate with about 5 per cent of free nitric acid.
The work is transferred to a cold dilute (say 5 per cent) solution of cupric sulphate slightly acidulated with sulphuric acid.
Thirty-five grammes ofcupric acetate are dissolved in a litre of water, and 20 cubic centimetres of the strongest liquid ammonia are added.
Covelli, who in 1839 observed crystals of cupric sulphide encrusting Vesuvian lava, the mineral having been formed here by the interaction of hydrogen sulphide and cupric chloride, both of which are volatile volcanic products.
Dissolve common verdigris or cupric hydrate in hot acetic acid, so as to form a highly concentrated solution; filter and place in a cool situation to crystallise.
By the calcination the sulphur in the compound is first oxidised, sulphate of sodium is formed, and at the same time the chlorine from the sodium chloride unites with the copper to form cupric chloride.
As we have already seen, Vogel proposed to obtain chlorine by the decomposition by heat of cupric chloride, and to reconvert the resulting cuprous chloride into the cupric salt by treatment with hydrochloric acid.
Silver nitrate and cupric sulphate in stick or strong solution should not be used; but sprays of dilute solutions (one or two grains to the ounce of distilled water), twice or thrice a day, are often of service.
The ammonio-cupric method used at the same time gave results of from .
Gerhard preferred undiluted tincture of the chloride of iron; Condie, cupric sulphate, thirty grains to the ounce.
Their walls should be distended with solutions of carbolic acid or be touched with solutions of iodine, silver nitrate, or cupric sulphate, to promote reparative inflammation.
Tannin, potassium chlorate, and cupricsulphate are often used for this purpose.
The best local application to the edges of the pharyngeal syphilitic ulcers is the solid cupric sulphate.
It is a cupric oxychloride, having the formula CuCl2.
As early as 1834, the chemist Runge observed the formation of a dark green color when heated aniline nitrate in the presence of cupric chloride.
Cupric arsenite, when heated, gives off arsenious acid and water, leaving a residue of arsenide of copper and copper arseniate.
It differs from Scheele's Green, or cupric arsenite, in being lighter, more vivid, and more opaque.
It is a cupric arsenite, with the common attributes of emerald green, under which name it is sometimes sold.
Slightly alkalize the distillate with potash, add a few drops of cupric sulphate, and afterwards just enough hydrochloric acid to dissolve the excess of cupric hydrate: white cuprous cyanide will remain undissolved.
With ammonio-cupric sulphate (prepared by similarly treating cupric sulphate), a bright green precipitate of cupric arsenite.
Soluble ferrocyanides give, with pure ferrous sulphate, a white precipitate turning blue in air; with ferric chloride a precipitate of Prussian blue; with cupric sulphate a maroon precipitate.
The use of cupric chloride is not advisable, as it corrodes lead, and gives rise to the formation of soluble chloride of lead, which complicates the separation of zinc from cadmium.
In "Miller's Chemistry" it is stated it "may be obtained by boiling solutions of arsenious anhydride andcupric acetate, and adding to the mixture an equal bulk of cold water.
It is stated in Watts' "Dictionary of Chemistry" that it is "prepared on a large scale by mixing arsenious acid with cupric acetate and water.
To a saturated solution of cupric nitrate may be added a small amount of a saturated solution of potassium permanganate, sufficient to give a decided purple color to the mixture.
A large excess of acid is liable to interfere with the precipitation of the ‹last traces› of cupric sulphide and is avoided in exact work.
In a solution ofcupric chloride, the chloride-ion is identical in every respect with the chloride-ion found in a solution of hydrochloric acid.
It will take some time for any cupric ions actually to reach the electrode and be deposited as metallic copper.
Cupric sulphide, however, is so insoluble that it may be precipitated completely from the solution by the addition of a sulphide (‹exp.
Polarization may be entirely avoided by the use of a silver nitrate solution and silver electrodes or of a cupric salt solution and copper electrodes (Noyes and Blanchard).
The hydrogen and the hydroxide ions are the fastest, in aqueous solutions, and their speeds are compared in the next experiment with that of blue cupric ions, which have a speed roughly the same as that of many common ions.
In modern terms, each hydrogen atom, present as an ion, has lost one electron, and each copper atom present in the form of a cupric ion has lost two electrons.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "cupric" in a variety of sentences. We hope that you will now be able to make sentences using this word.
