Izinto ezimunca amakhemikhali zingakwazi ukumunca uketshezi oluhlukahlukene lwamakhemikhali noketshezi olubolayo, zilawule ngempumelelo futhi ngokushesha futhi zihlanze ukuchitheka kwamakhemikhali, zinciphise umonakalo obangelwa ukuchitheka kwamakhemikhali, zinciphise isikhathi sokuchayeka kwabasebenzi ezintweni eziyingozi, futhi zinikeze isiqinisekiso sokuphepha komuntu siqu.