$K _3\left[ Co \left( NO _2\right)_6\right]$ very poorly water soluble
$\left( NH _4\right)_3\left[\right.$ As $\left( MO _3 O _{10}\right)_4$ ] water insoluble ammonium arseno molybdate
$\left[ Fe _3( OH )_2( OAc )_6\right] Cl$ is water soluble.
........ રજૂ કરે છે.