Fórmanse  pola

 oxidación  dos

 sulfuros  cando

Pronom

  estes

Determinador

  entran

Verb

  en

Adposició

 contacto  co

  osíxeno

substantiu

  do

  aire

substantiu

.

They are formed by the oxidation of sulfides when they come in contact with air oxygen.

They are formed by the oxidation of sulfides when they come in contact with air oxygen.