W·m −1 ·K −1 Bulk modulus 7.7 GPa Mohs hardness 2.0 CAS registry number 7704-34-9 Most stable isotopes Main article: Isotopes of sulfur iso N.A. half-life DM DE ( MeV ) DP 32 S 95.02% 32 S is stable with 16 neutrons 33 S 0.75% 33 S is stable with 17