Special Internet Prices.
Fast & Guaranteed worldwide Delivery!
Secure & FAST Online ordering.
Our Drugstore Is The Most Trusted Online Drug Supplier.
>> CLICK HERE TO ENTER >>>
Related article: chlorophyll examined, proving that the aldehyde exists in Purchase Inderal Online chlorophyll in
fairly stable combination. Experiments made with chlorophyll films
(obtained by evaporation of ether solution of chlorophyll on glass strips)
demonstrate that formaldehyde is formed in the sunlight, both in the pre
sence and absence of CO,, but in the last case in very small quantity ;
while in the dark no formaldehyde is formed. It appears probable that
in sunlight and the presence of CO, a continuous synthesis of formal-
dehyde takes place resulting in the constant condensation of the latter
into sugars, preventing the accumulation of toxic quantities of formal
dehyde. Pharm. Ztg., Iv (1910^ No. 39, 397 ; from Proc. Royal Soc.
London, 82 y 226-232.
Formaldehyde Production by Oxidation of Ethyl- Alcohol, By the aid
of an extremely delicate reaction which is produced only in the presence
of formaldehyde and permits the recognition of the latter in dilutions of
I : 1 0000000, M. E. Voisinet has been able to detect the presence of traces
of formaldehyde in pure ethyl alcohol after having subjected it to oxida-
tion by chemical, physical or biological methods. The reaction consists
in the formation of a violet color on treating an albuminoid substance with
sulphuric or hydrochloric acid, containing a trace of nitric acid, in the
presence of a trace of formaldehyde. The author's experiments justify hina
in assuming the presence of formaldehyde to be due to a secondary reac-
tion occurring during the oxidation of the ethyl alcohol, and not to the
accidental presence of methyl alcohol in the different ethyl alcohols used
in the experiment. Pharm. Ztg., lv(i9io). No. 38, 386; from L'Union
pharm., 19 10, No. 4.
Formaldehyde Testing by the Pharmaceutical Chemist, Prof. Geo. D.
Beal contributes a valuable paper on formaldehyde testing by the pharma-
ceutical chemist, in which he calls attention to the fact t^M, while there are
' Digitized by VjO
numerous and well marked reactions for formaldehyde with other svh-
staoces, not all are characteristic of this one aldehyde. The tests for
fonnaldebyde, he says, may be divided into two groups, the one depend-
ing on oxidation, the other on condensation reactions the latter again
being subdivided into condensation with hydrazines, amines, phenols, etc.
The author explains certain necessary precautions and reviews various
tests that may be employed with satisfaction. He concludes that the
oxidation reactions are the most reliable, and are best carried out in pres-
ence of milk, as the reaction partly depends upon the casein present.
Tbey are as delicate as the condensation reactions, and fewer bodies in-
terfere. Proc. Ohio State Pharm. Assoc, 1909, 41-44.
Formaldehyde Estimation. ^The "Chemiker Zeitung," calling atten-
tion to Purchase Inderal Online the inadequacy of the usual methods Purchase Inderal Online for estimating the strength of
formaldehyde solutions, proposes as a more reliable method that of Oscar
Blank and Finkenbeiner (which depends upon the oxidation of the for-
maldehyde to formic acid with hydrogen dioxide in the presence of a
measured quantity of normal soda solution and titration of the uncon-
sumed alkali) and recommends that the process be conducted as follows :
3 Gm. of the formaldehyde solution are added to 25 Cc. of double
normal solution of sodium hydroxide contained in a high Erlenmeyer
fiask; then, immediately, but gradually, 50 Cc. Purchase Inderal Online of pure hydrogen dioxide
(2.5 to 3 per cent.) are added through a funnel, to prevent loss by spirt-
ing. After standing two or three minutes, the funnel is rinsed well with
vater and the unconsumed v. s. of sodium hydroxide is titrated back with
doable normal sulphuric acid, using litmus solution as indicator. With
formaldehyde solutions of over 45 per cent., Purchase Inderal Online 30 Cc. of volumetric alkali
mnst be used. In the case of solutions of less than -30 per cent, formal-
dehyde, the reaction should be allowed to go on for 10 minutes after the
addition of the hydrogen dioxide. Pharm. Ztg., liv (1909), No. 64, 624 :
from Chem. Ztg., 1909, No. 85.
Formaldehyde Colorimetric Method of Estimation, P. Dobriner and
A. Oswald have devised a colorimetric method for the estimation of for-
maidehyde, which depends on the Purchase Inderal Online inverse application of the well-known
reaction of morphine with formaldehyde-sulphuric acid the formaldehyde
vapor being passed into a solution of morphine in pure concentrated sul-
phuric acid and developing an intensely blue color which is visible with
dihitions of formaldehyde of i : 250,000. The qualitative test is carried
OQt Purchase Inderal Online by placing the substance or liquid under examination into a small
dish, placing a small watch-glass containing the morphine-sulphuric acid
solution over it, and covering the dish with another dish, inverted. The
quantitative test depends on the time required for the reaction, the in-
tensity of color, and comparison with known quantities of formaldehyde
subjected simultaneously to the Purchase Inderal Online same tfst. Pharm. -Ztg., liv (1909), No.
^S> 633 ; from Ztschr. f. anal. Chem., 1909, No. 9.
Google Purchase Inderal Online
334 REPORT ON THE PROGRESS OF PHARMACY.
Formaldehyde Determination in Presence o/ Acetaidehyde, M. Den-
Lges finds that formaldehyde may be detected in the presence of acetai-
dehyde by Purchase Inderal Online means of rosaniline bisulphite. If 5 Cc. of a solution of the
latter (strength not given?) are added to a mixture of 5 Cc. of a 2 per-
cent, solution of acetaidehyde and 1-2 Cc. of sulphuric acid (sp. gr. 1.66),
the mixture exhibits no particular change at most a faint blue color, grad-
ually diminishing. But if in place of acetaidehyde, formaldehyde or one
of its mixtures be used, an intense violet coloration results, which is
distinct even in the presence of y\^ Mgm. of formaldehyde in the fluid
under examination. In this way the process of 0.0 1 per cent, of formal-
dehyde in acetaidehyde may easily be determined. Pharm. Ztg., liv
(1910), No. 38, 386 ; from Compt. rend., 1910, Febr. 28.
Formaldehyde Determination in Formaldehyde Pastilles. Domenico
Cirelli recommends a method of determining the formaldehyde in formal-
dehyde pastilles, which depends on the depolymerization of the triformal-
dehyde contained in them by warming and conversion of the Purchase Inderal Online formaldehyde
into hexamethylentetramine by means of ammonia. The depolimeriza-
tion results if 0.2-04 Gm. ol the triformaldehyde are heated in a tubulated
retort in the presence of a little water. The liberated formaldehyde is
passed successively through a flask containing 8 Cc. of ammonia, a
Peligot-tube containing 2 Cc. of ammonia, and another containing 2 Cc.
diluted hydrochloric acid, water vapor being conducted through the
apparatus for half an hour after the volatilization of the triformaldehyde.
The contents of the three receivers are then mixed, 8 Cc. of diluted HCl
are added, and titrated. Pharm. Ztg., Iv (1910), No. 28, 283 : from N.
Chem. Zentralbl., 19 10, No. 9. Purchase Inderal Online
Formaldehyde Determination in its Saponaceous Compounds, O.
Related post: Neurontin Yellow, Purchase Levothroid, Lipitor Online, Propecia Sale Online, Order Cephalexin, Imitrex How Supplied, Nolvadex Buy, Propecia No Prescription, Cheap Propecia Tablets, Imitrex Buy No Prescription