a gas, H2S, with an odour of rotten eggs; r.d. 1.54 (liquid); m.p. -85.5°C; b.p. -60.7°C. It is soluble in water and ethanol and may be prepared by the action of mineral acids on metal sulphides, typically hydrochloric acid on iron(II)sulphide... In acid solution hydrogen sulphide is a mild reducing agent. Hydrogen sulphide has an important role in traditional qualitative chemical analysis, where it precipitates metals with insoluble sulphides... Hydrogen sulphide is exceedingly poisonous., H2S (van. nimetus väävelvesinik) mädamunalõhnaga mürgine värvuseta gaas; ... veeldub kergesti ..., vees lahustudes moodustab nõrga v.-happe. Looduses leidub vesiniksulfiidi peamiselt nafta- ja maagaasimaardlates, vulkaanilises gaasis ja mineraalvees.