Molecular Structure and Properties
Hydrazine forms a monohydrate that is more dense (1.032 g/cm3) than the anhydrous material.
Hydrazine can arise via coupling a pair of ammonia molecules by removal of one hydrogen per molecule. Each H2N-N subunit is pyramidal in shape. The N-N distance is 1.45 Å (145 pm), and the molecule adopts a gauche conformation. The rotational barrier is twice that of ethane. These structural properties resemble those of gaseous hydrogen peroxide, which adopts a "skewed" anticlinal conformation, and also experiences a strong rotational barrier.
Hydrazine has basic (alkali) chemical properties comparable to those of ammonia:
- N2H4 + H2O → + + OH−
with the values:
- Kb = 1.3 x 10−6
- pKa = 8.1
(for ammonia Kb = 1.78 x 10−5)
Hydrazine is difficult to diprotonate:
- + + H2O → 2+ + OH− Kb = 8.4 x 10−16
The heat of combustion of hydrazine in oxygen (air) is 194.1 x 105 J/kg (9345 BTU/lb).
Read more about this topic: Hydrazine
Famous quotes containing the words structure and/or properties:
“There is no such thing as a language, not if a language is anything like what many philosophers and linguists have supposed. There is therefore no such thing to be learned, mastered, or born with. We must give up the idea of a clearly defined shared structure which language-users acquire and then apply to cases.”
—Donald Davidson (b. 1917)
“The reason why men enter into society, is the preservation of their property; and the end why they choose and authorize a legislative, is, that there may be laws made, and rules set, as guards and fences to the properties of all the members of the society: to limit the power, and moderate the dominion, of every part and member of the society.”
—John Locke (1632–1704)