Kuidas palju do temperatuur mõõtmised mõjutamine pH täpsus?
Temperatuur muutused igaüks pH väärtus for pH elektroodid by {{{0}}.{{}}3pH/ degree . For instance, a pH meter of grade 0}.2 is kalibreeritud in a pH puhver at 30 kraad ja seejärel testitud at 60 kraad (eeldades the pH of the solution vahemikud from pH 6 to 8) If pH7.00} and pH7.00 differ by one pH unit% 2c the maximum error caused by temperature is 30 0.{003=0.09 pH. The largest error is 0.27 pH if it is 3 pH units (between pH 4 and 10), which show that temperature has a significant impact on pH. Of course, we can make inferences from it as well. We should a aware of the following three factors in order to minimize the in temperature to pH mõõtmine:
(1) kalibreerida the pH meter, try to use a buffer lahus et on lähedal pH of the solution to be testida.
(2) valmistamine an pingutus säilitada kalibreerimine lahus's temperatuur at, või väga ligilähedane, see mõõdetud lahus.
(3) peaksite valima a pH meeter koos temperatuur kompensatsioon.
Temperatuur kompensatsioon reguleerimine on ainult saadaval on pH meetrid koos täpsusega suurem kui {{{{0}.1pH; pH meetrid koos a hinne of 0.2 do not. Some pH meters with 0}.2-grade accuracy also advertising 0}.{{7}grade accuracy. This is actually not doable. Some individuals mix up the terms "resolution {{1{{{13}% 7d}}.1pH" with "accuracy 0.1pH." The pH inaccuracy at a distance of 60 degree , even in terms of one pH unit, is 0.00360=0.18pH. Järelikult, a pH meeter's maksimaalne täpsus ilma temperatuur korrektsioon on ainult 0,2pH.
