For a single solute, the Norrish equation reduces to:
Raoult's Law is very accurate within the range of 0.95 to 1.0 water activity, whereas the Norrish equation is reasonably accurate down to about 0.55.
This program calculates the Norrish constant for a solute.
This program uses a modified Norrish equation. The author has found that by applying an activity coefficient (A) to the molecular weight (mwt), a more accurate water activity estimation is possible. When calculating the solute mole fraction Xi, mwt is replaced with mwt/A. A is generally less than 1, and is calculated by this program, as well as the value of the Norrish constant k.
eg:Dissociation species = 2
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