Search results
Results from the WOW.Com Content Network
A solution of 4-nitrophenol appears colorless below pH 5.4 and yellow above pH 7.5. [3] This color-changing property makes this compound useful as a pH indicator . The yellow color of the 4-nitrophenolate form (or 4-nitro phenoxide ) is due to a maximum of absorbance at 405 nm (ε = 18.3 to 18.4 mM −1 cm −1 in strong alkali). [ 4 ]
Main page; Contents; Current events; Random article; About Wikipedia; Contact us
with the formula HOC 6 H 4 NO 2.Three isomeric nitrophenols exist: . o-Nitrophenol (2-nitrophenol; OH and NO 2 groups are neighboring, a yellow solid.; m-Nitrophenol (3-nitrophenol, CAS number: 554-84-7), a yellow solid (m.p. 97 °C) and precursor to the drug mesalazine (5-aminosalicylic acid).
For general purposes, buffers at pH 4.00 and pH 10.00 are suitable. The pH meter has one calibration control to set the meter reading equal to the value of the first standard buffer and a second control to adjust the meter reading to the value of the second buffer. A third control allows the temperature to be set.
The pH value of a neutral solution is 7.0 at 25°C (standard laboratory conditions). Solutions with a pH value below 7.0 are considered acidic and solutions with pH value above 7.0 are basic. Solutions with a pH value below 7.0 are considered acidic and solutions with pH value above 7.0 are basic.
Nitro compound hydrogenation. The α-carbon of nitroalkanes is somewhat acidic. The pK a values of nitromethane and 2-nitropropane are respectively 17.2 and 16.9 in dimethyl sulfoxide (DMSO) solution, suggesting an aqueous pK a of around 11. [22] In other words, these carbon acids can be deprotonated in aqueous solution.
Nitrobenzene is an aromatic nitro compound and the simplest of the nitrobenzenes, with the chemical formula C 6 H 5 NO 2. It is a water-insoluble pale yellow oil with an almond-like odor. It freezes to give greenish-yellow crystals. It is produced on a large scale from benzene as a precursor to aniline.
Structural formula of nitroso group. In organic chemistry, nitroso refers to a functional group in which the nitric oxide (−N=O) group is attached to an organic moiety.As such, various nitroso groups can be categorized as C-nitroso compounds (e.g., nitrosoalkanes; R−N=O), S-nitroso compounds (nitrosothiols; RS−N=O), N-nitroso compounds (e.g., nitrosamines, RN(−R’)−N=O), and O ...