Solid phase
Official name
Ammonium hydrogen sulfate (phase III)
Secondary names
Ammonium bisulfate; azanium;hydrogen sulfate; Ammonium hydrogensulphate; Sulfuric acid, monoammonium salt; Acid ammonium sulfate; Monoammonium sulfate; (NH4)HSO4; (NH4)HSO4; (NH4)HSO4-III; (NH4+)HSO42-; H5NO4S
CAS number
7803-63-6
Family
ionic solid
Class
acid salt
Compound type
sulfate
Formula
(NH+4)HSO4
Chemical formula
(NH4)HSO4
Elemental formula
(N+) H5 S O3 (O-)
Isotope mixture type
terrestrial abundance
4.0
  Formula Name Family Number min-max Mole fraction Isotope mole fraction State Relevance
NH+4 Ammonium ion molecule 1 0.5 1 constituent cation main
HSO4 Hydrogen sulfate ion molecule 1 0.5 1 constituent anion main
Chemical functions
  Function Number
H4>∣N+ 1
Chemical bonds
  Bond Number
>∣N+O 1
N+H 4
SO 1
2
-\gg S-O- 1
-O-H 1
Class
acid salts (05)
Type
simple acid salts (05.01)
Group
sulfate (05.01.09)
Phase name
Ammonium hydrogen sulfate-III
Phase type
crystalline
Crystal system
monoclinic
Crystal class
prismatic
Crystal class symbol
2/m (C2h)
Crystal spacegroup
P2(1)/c
Comments
paraelectric phase
Molar mass
115.109 g/mol
Density
1.787 g/cm^3
State NTP
solid
Phase transitions
Phase transition type Other phases Temperature - Pressure
solid-liquid liquid decompose at 120 °C (393 K)
solid-solid (NH4)HSO4-II below -3°C (270 K)
Phase transitions comments
ferroelectric to nonferroelectic phase transition at 154K
Refringence type
biaxial
Pure color
colorless
Color
colorless, white
Diaphaneity
transparent to translucent