Site na afọ nke ahụmịhe na nyocha nyocha kemịkal kemistri , nwere ike iwepụta ọtụtụ nyocha . kemịkalụ nwere izute ọtụtụ ngwa ike . Na mgbakwunye na ndepụta ngwaahịa dị n'okpuru, ị nwekwara ike hazie onye nyocha nke gị pụrụ iche dịka mkpa gị ka mkpa.