Question

How to calculate the water content using the temperature and Aw

Answer 1

Water activity (A_w) = partial vapor pressure of water in a substance / standard state partial vapor pressure of water

For pure distilled water, A_w = 1

In general, as the temperature increases, A_w increases, as a result, the water content increases.

At equilibrium, the relationship between water content and equilibrium humidity of a material can be shown graphically by a curve, i.e. moisture sorption isotherm. For each humidity value, a sorption isotherm indicates the corresponding water content value at a given temperature.The relationship between water content and water activity (a_w) is complex. An increase in a_w is usually accompanied by an increase in water content, but in a non-linear fashion. This relationship between water activity and moisture content at a given temperature is called the moisture sorption isotherm.