Rapid Micromethod for Determining Carbon and Hydrogen in Organic Compounds

Backeberg, O. G.; Israelstam, S. S.

doi:10.1021/ac60067a045

Cited by 15 publications

(3 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The sheets are run down flow overnight in a tightly sealed cabinet using as solvent a mixture of 50 volumes of n-butyl alcohol, 30 volumes of pyridine, 30 volumes of water, and 4.5 volumes of benzene. This solvent possesses an objectionable odor and may be replaced by one suggested by Albon and Gross (2) with satisfactory results. However, the low Rf values of sucrose and raffinose in this solvent make it desirable to run the chromatogram a minimum of 18 hours when raw beet juice is under test.…”

Section: Determination Of Raffinosementioning

confidence: 96%

“…MANY attempts have been made to replace the troublesome lead peroxide by an alternative absorbent for nitrogen oxides in the microcombustion of organic compounds containing nitrogen. These variations in the carbon-hydrogen determination have been reviewed by Elving and McElroy (7), by Belcher and Ingram (5) and, most recently, by Backeberg and Israelstam (2). Opinions are divided between those who believe that nitrogen oxides should be removed in the absorption train, and those who recommend absorption or destruction of the nitrogen oxides within the combustion tube.…”

mentioning

confidence: 99%

“…Despite opinions to the contrary (2), nitrogen oxides may be removed satisfactorily by absorbents outside the combustion tube (18). Such absorbents are interposed between the water and the carbon dioxide absorption tube.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Replacement of Lead Peroxide in Carbon, Hydrogen Microdetermination

Cross¹,

Wright²

1954

Anal. Chem.

View full text Add to dashboard Cite

The neocupferron titration curve illustrates the same mode of behavior, although somewhat less clearly. High-frequency titration of praseodymium chloride verifies the intermediate formation of the 1 to 1 complexes, MCup + + and M(NeoCup) + t. CONCLUSIONSCupferron and neocupferron seem to be excellent precipitating agents for the rare earth ions, provided that no interfeiing substances are present in the solution. Since cupferron and neocupferron are fairly general precipitating agents for many metal ions, it is obvious that they cannot compete with oxalic acid when the rare earth ions are to be separated from other impurities. However, in the absence of impurities and when only a small amount of rare earth is present in solution (2 to 50 mg.), the relatively large volume of precipitate and the ease with which it can be washed and filtered make the determination somewhat more accurate than the oxalate precipitation.Apparently, under precipitation conditions describe here, considerable amount of coprecipitation makes it impossible to determine accurately the amount of the rare earth present from the weight of the dried precipitate. However, ignition to the oxide is rapid and yields very satisfactory results. ACKNOWLEDGMENTThe assistance of George E. Knudson in obtaining the absorption spectra of the rare earth solutions is gratefully acknowledged.

show abstract

Section: Determination Of Raffinosementioning

confidence: 96%

mentioning

confidence: 99%