Compound of hydrogen sulfide with phenylhydrazine

Summary

• 1. The melting point diagram of the system C₆H₅NH · NH₂ -H₂S has been determined by the method of thermal analysis. No clearly defined maximum has been found in the system. The curve for the composition passes through a transition point at which the maximum aril eutectic point coincide and correspond to a composition of 33.3 mole-% of H₂S at 1.4 + 0.1 . which is that re quired by the compound (C₆H₅NH · NH₃)₂S,

• 2. The t-p diagram has been determined La the presence of three phases (solid, liquid, and gas), so that, when determining the melting point diagram, a correction could be introduced for the amount of volatile component remaining in the gas phase.

• 3. The dissociation pressure of the solid compound (dissociating into solid phenylhydrazine and gaseous H₂S) has been determined. At 0° the dissociation pressure is 3.3 atm, thus indicating the low stability of this compound.

  The heat of formation of the compound from solid phenylhydrazine and gaseous H₂S has been determined from dissociation pressure data, the value obtained being 8500 cal/mole.

• 4. It has been shown that radon is not isomorphously coprecipitated with the compound formed by phenylhydrazine with H₂S and does not form an analogous compound with phenylhydrazine. The compound obtained, therefore, cannot be assigned to the class of molecular compounds, but must be regarded as an ammonium compound, i.e., of the type(C₆H₅NH\sdNH₃)₂S.