Hyponitrous acid
Encyclopedia
Hyponitrous acid is the chemical compound H2N2O2. This can be formulated as HON=NOH and is an isomer of nitramide
, (H2N−NO2). It forms white crystals that are explosive when dry. There are two possible structures, trans and cis, and the solid is believed to be the trans form.
Hyponitrous acid is a weak acid (pk1 = 7.21, pK2= 11.54) in aqueous solution and decomposes to N2O
and water with a half-life
of 16 days at 25°C at pH 1-3.
As this reaction is not reversible N2O should not be considered as the anhydride of H2N2O2.
Hyponitrous acid forms two series of salts, the "acid hyponitrites" containing [HON=N]− anion and hyponitrite
s containing the [ON=NO]2− anion.
Hyponitrous acid can be prepared from silver hyponitrite and anhydrous HCl in ether:
Silver hyponitrite can be prepared by the reduction of sodium nitrite
:
Nitramide
Nitramide, H2NNO2, is a chemical compound. Organyl derivatives of nitramide, RNHNO2 are termed nitroamines, and are widely used as explosives: examples include RDX and HMX.- Structure :...
, (H2N−NO2). It forms white crystals that are explosive when dry. There are two possible structures, trans and cis, and the solid is believed to be the trans form.
Hyponitrous acid is a weak acid (pk1 = 7.21, pK2= 11.54) in aqueous solution and decomposes to N2O
Nitrous oxide
Nitrous oxide, commonly known as laughing gas or sweet air, is a chemical compound with the formula . It is an oxide of nitrogen. At room temperature, it is a colorless non-flammable gas, with a slightly sweet odor and taste. It is used in surgery and dentistry for its anesthetic and analgesic...
and water with a half-life
Half-life
Half-life, abbreviated t½, is the period of time it takes for the amount of a substance undergoing decay to decrease by half. The name was originally used to describe a characteristic of unstable atoms , but it may apply to any quantity which follows a set-rate decay.The original term, dating to...
of 16 days at 25°C at pH 1-3.
- H2N2O2→ H2O + N2O
As this reaction is not reversible N2O should not be considered as the anhydride of H2N2O2.
Hyponitrous acid forms two series of salts, the "acid hyponitrites" containing [HON=N]− anion and hyponitrite
Hyponitrite
A hyponitrite refers to ionic compounds that contain the hyponitrite ion, N2O22−, or to organic hyponitrites , for example di-tert butyl hyponitrite.-Hyponitrite ion:There are cis and trans forms of the hyponitrite ion...
s containing the [ON=NO]2− anion.
Hyponitrous acid can be prepared from silver hyponitrite and anhydrous HCl in ether:
- Ag2N2O2 + 2 HCl → H2N2O2 + 2 AgCl
Silver hyponitrite can be prepared by the reduction of sodium nitrite
Sodium nitrite
Sodium nitrite is the inorganic compound with the chemical formula NaNO2. It is a white to slight yellowish crystalline powder that is very soluble in water and is hygroscopic...
:
- 2 NaNO2 + 4 NaHg + 2 H2O + 2 AgNO3 → Ag2N2O2 + 2 NaNO3 + 4 NaOH + 4 Hg