Relative humidity-temperature relationships of some saturated salt solutions in the temperature range 0 degree to 50 degrees C

Abstract

The relative humidity-temperature relationships have been determined in air in equilibrium with saturated salt solutions of lithium chloride. LiCl. H 2 O; magnesium chloride, MgCl 2 . 6H 2 O; sodium dichromate, Na 2 Cr 2 O 7 .2H 2 O; magnesium nitrate, Mg(NO 3 ) 2 . 6H 2 O; sodium chloride, NaCl; ammonium sulfate, (NH 4 ) 2 SO 4 ; potassium nitrate, KNO 3 ; and potassium sulfate, K 2 SO 4 , over a temperature range of 0° to 50°C, using the dewpoint method. The relative humidity is a continuous function of temperature, and, except for sodium chloride, is monotonic. The curve for sodium chloride increases from 74. 9 percent relative humidity at 0°C to a maximum of 75.6 percent at 30°C and then gradually decreases to 74.7 percent. The maximum change in relative humidity with temperature, about 15 percent relative humidity as the temperature increases from 0° to 50°C, occurs with saturated salt solutions of sodium dichromate and magnesium nitrate.