To about 1 mL of 0.5 M mercury (I) nitrate, Hg2(NO3)2,
solution add about 1 mL of dilute HCl and mix. Record your observations.
Centrifuge and separate the precipitate from the solution. Discard the solution.
Add about 2 mL of distilled water and stir to wash the precipitate. Centrifuge
and discard the solution.
Add about 1 mL of concentrated ammonium hydroxide, NH4OH,
(located in the fume hood) to the precipitate.
The formation of a black or grey precipitate confirms
the presence of mercury (I) ions. The precipitate is a mixture of elemental
mercury, Hg, and the white compound called mercury (II) amido chloride,
HgNH2Cl. Record your observations.