Isiqa

Isiqa noma isiqa sevanga siwuhlobo lotho esinesakhiwo sevanga esingaguquki nezakhi eziyisici saso. Amanye amaphatho anezela ngokuthi isiqa asinakuhlukaniswa ngezinhlwa eziyisakhi saso nganoma iyiphi indlela yokuhlukanisa, okungukuthi, ngaphandle kokusiphula izibhonqi zevanga. Iziqa ziyatholakala kuyiziqa ezilula, noma imixube yevanga, noma iziqungo (alloys). Izinhlwa zevanga kungenzeka zibandakanywe noma zingabandakanywa kuncasiselo, okuyinto encike embonweni wengcweti.

Iziqa zevanga imvama zibizwa ngokuthi "ezicwebile" ukuzihlukanisa ezimvubweni. Isibonelo esivamile sesiqa sevanga amanzi acwebile; anezakhi ezifanayo zeqhatho elifanayo lehwanzi nesOhwe kungakhathaliseki ukuba agonqwe kude nomfula noma enziwe engqalabeni (laboratory). Ezinye iziqa ezitholakala ngesimo esicwebile idayimani (umcalahle), imbedu, itswayi (inaside chwenzi) noshukela okhumuziwe (isincishuko). Nokho, eqinisweni, asikho isiqa esicwebile ngokugcwele, futhi ukucweba kwesiqa kungacaciswa ngokuqondene nokusebenza kwaso.

Iziqa sevanga zitholakala zimkhumenqe, ziwuketshezi, ziwuhowo, noma ziwunyazani, futhi zingaguquka phakathi kwezimo zotho lapho kuguquka izinga lokushisa noma umfutho nesikhathi. Iziqa zingahlanganiswa nezinye noma ziguqulwe kwezinye ngokulumbana kweziqa.