電(dian)(dian)(dian)解(jie)質(zhi)是(shi)溶于水溶液(ye)中或在熔融狀態下(xia)就能夠導電(dian)(dian)(dian)的化合物。根據其電(dian)(dian)(dian)離程(cheng)度可分(fen)為強電(dian)(dian)(dian)解(jie)質(zhi)和弱電(dian)(dian)(dian)解(jie)質(zhi),幾乎全部電(dian)(dian)(dian)離的是(shi)強電(dian)(dian)(dian)解(jie)質(zhi),只有少部分(fen)電(dian)(dian)(dian)離的是(shi)弱電(dian)(dian)(dian)解(jie)質(zhi)。
電(dian)(dian)解質(zhi)都(dou)是以離(li)子(zi)(zi)鍵或(huo)極性(xing)共(gong)價鍵結合的物(wu)質(zhi)。化(hua)(hua)合物(wu)在(zai)溶解于(yu)水中(zhong)或(huo)受熱狀態下能夠(gou)解離(li)成(cheng)自由移動的離(li)子(zi)(zi)。離(li)子(zi)(zi)化(hua)(hua)合物(wu)在(zai)水溶液(ye)中(zhong)或(huo)熔化(hua)(hua)狀態下能導電(dian)(dian);某些共(gong)價化(hua)(hua)合物(wu)也能在(zai)水溶液(ye)中(zhong)導電(dian)(dian),但(dan)也存在(zai)固(gu)體電(dian)(dian)解質(zhi),其導電(dian)(dian)性(xing)來源于(yu)晶格中(zhong)離(li)子(zi)(zi)的遷移。
電解質分類:
強電解質
一(yi)般有:強酸(suan)、強堿(jian),活潑金(jin)屬氧化物和大多數鹽,如:硫(liu)酸(suan)、鹽酸(suan)、碳酸(suan)鈣、硫(liu)酸(suan)銅等。
弱電解質
一般有:弱酸、弱堿,少部(bu)分鹽,如:醋酸、一水合(he)氨(an)(NH3·H2O)、醋酸鉛、氯(lv)化汞(gong)。另外,水是極弱電解(jie)質。
硫(liu)酸(suan)鋇(bei)在(zai)水溶液中(zhong)是沉淀,只是在(zai)水中(zhong)的溶解(jie)度很(hen)(hen)(hen)小很(hen)(hen)(hen)小,但是盡管硫(liu)酸(suan)鋇(bei)在(zai)水中(zhong)難(nan)溶并不代表在(zai)水中(zhong)一點(dian)也不溶解(jie),在(zai)水中(zhong)溶解(jie)的很(hen)(hen)(hen)少的那(nei)部分依然是完全電(dian)離的,而且在(zai)熔融狀態下能導電(dian),所以是電(dian)解(jie)質(zhi) ,而且是強電(dian)解(jie)質(zhi)。