title: Paratungstate
text: # Paratungstate
  
  In chemistry, paratungstate refers to the anion with the formula $[W_{12}O_{42}]^{12-}$ and salts derived from this anion. The term also refers to protonated derivatives of this anion, including $[H_2W_{12}O_{42}]^{10-}.$ Ammonium paratungstate (or APT), $(NH_4)_{10}[H_2W_{12}O_{42}]$ is a key intermediate in the purification of tungsten from its ores.
  
  The salt $(NH_4)_{10}(W_{12}O_{42})·4H_2O$ has been characterized by X-ray crystallography.
  
  The unprotonated anion $[W_{12}O_{42}]^{12-}$ has $C_{2h}$ symmetry.
  
  