ORP氧化還(huan)原電(dian)極

ORP氧(yang)(yang)化還(huan)(huan)(huan)原(yuan)(yuan)(yuan)電(dian)(dian)(dian)(dian)極是用來反映水溶液中所有物(wu)(wu)質(zhi)表(biao)現出來的宏觀氧(yang)(yang)化還(huan)(huan)(huan)原(yuan)(yuan)(yuan)性(xing)。氧(yang)(yang)化還(huan)(huan)(huan)原(yuan)(yuan)(yuan)電(dian)(dian)(dian)(dian)位越(yue)高(gao)，氧(yang)(yang)化性(xing)越(yue)強，氧(yang)(yang)化還(huan)(huan)(huan)原(yuan)(yuan)(yuan)電(dian)(dian)(dian)(dian)位越(yue)低，還(huan)(huan)(huan)原(yuan)(yuan)(yuan)性(xing)越(yue)強。電(dian)(dian)(dian)(dian)位為(wei)正表(biao)示溶液顯(xian)示出一定的氧(yang)(yang)化性(xing)，為(wei)負則表(biao)示溶液顯(xian)示出一定的還(huan)(huan)(huan)原(yuan)(yuan)(yuan)性(xing)。氧(yang)(yang)化還(huan)(huan)(huan)原(yuan)(yuan)(yuan)電(dian)(dian)(dian)(dian)位對一個水體(ti)來說，往(wang)往(wang)存(cun)在多種氧(yang)(yang)化還(huan)(huan)(huan)原(yuan)(yuan)(yuan)電(dian)(dian)(dian)(dian)對，構成復(fu)雜的氧(yang)(yang)化還(huan)(huan)(huan)原(yuan)(yuan)(yuan)體(ti)系(xi)，而其氧(yang)(yang)化還(huan)(huan)(huan)原(yuan)(yuan)(yuan)電(dian)(dian)(dian)(dian)位是多種氧(yang)(yang)化物(wu)(wu)質(zhi)與還(huan)(huan)(huan)原(yuan)(yuan)(yuan)物(wu)(wu)質(zhi)發(fa)生氧(yang)(yang)化還(huan)(huan)(huan)原(yuan)(yuan)(yuan)反應的綜合結果。

不論反應(ying)形(xing)式如何，所謂(wei)(wei)氧化即失去(qu)電(dian)子(zi)，所謂(wei)(wei)還(huan)原即得到(dao)電(dian)子(zi)，一定伴有電(dian)子(zi)的(de)(de)(de)授受過程(cheng)。當將鉑金(jin)電(dian)極(ji)插入可逆的(de)(de)(de)氧化還(huan)原系統(tong)中，就(jiu)會將電(dian)子(zi)給與電(dian)極(ji)，并成(cheng)為與該系的(de)(de)(de)還(huan)原能力大(da)小相應(ying)電(dian)位的(de)(de)(de)半電(dian)池。將它與標準氫電(dian)極(ji)組合所測得的(de)(de)(de)電(dian)位即為該系的(de)(de)(de)氧化還(huan)原電(dian)位。

測量方法：

ORP測(ce)量電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)與pH測(ce)量電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)相(xiang)同，但使用(yong)貴金屬(shu)代替玻璃電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)作(zuo)為測(ce)量元件(jian)。使用(yong)惰性金屬(shu)是因(yin)為它(ta)們不會參與化(hua)學反應，最常(chang)(chang)見(jian)的(de)是，測(ce)量電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)由鉑制成，也可以使用(yong)其他高貴金屬(shu)，如黃金或白銀。當(dang)指(zhi)示(shi)(shi)電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)浸泡在(zai)含氧化(hua)和還原劑(ji)的(de)水(shui)中(zhong)時，ORP傳(chuan)感(gan)器產生(sheng)非常(chang)(chang)小(xiao)的(de)電(dian)(dian)(dian)(dian)壓(ya)(ya)，此電(dian)(dian)(dian)(dian)壓(ya)(ya)在(zai)指(zhi)示(shi)(shi)電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)（正(zheng)極(ji)(ji)(ji)的(de)鉑電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)）和參比(bi)電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)（負極(ji)(ji)(ji)）之間(jian)測(ce)量，中(zhong)間(jian)有水(shui)。探頭的(de)測(ce)量電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)（+）通常(chang)(chang)由鉑制成，參考電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)（-）通常(chang)(chang)由銀制成，周圍環(huan)繞著電(dian)(dian)(dian)(dian)解質溶液。兩(liang)個電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)之間(jian)的(de)電(dian)(dian)(dian)(dian)壓(ya)(ya)差實(shi)際上是ORP傳(chuan)感(gan)器的(de)輸出。一個氧化(hua)劑(ji)被添加(jia)(jia)到水(shui)中(zhong)，它(ta)獲得電(dian)(dian)(dian)(dian)子從鉑測(ce)量電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)的(de)表面，導致電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)變得越(yue)來越(yue)正(zheng)電(dian)(dian)(dian)(dian)荷。當(dang)您繼續(xu)向水(shui)中(zhong)添加(jia)(jia)氧化(hua)劑(ji)時，電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)會產生(sheng)更高和更高的(de)正(zheng)電(dian)(dian)(dian)(dian)壓(ya)(ya)。