Atmospheric Noble Gases and Their Dissolution in Water

2 Atmospheric Noble Gases and Their Dissolution in Water 

The atmosphere is a well-mixed reservoir with known concentrations of noble gases (Table 13.1). These atmospheric noble gases have characteristic isotopic abundances that are given in Table 13.2. The solubility of the noble gases is given in Fig. 13.1, expressed in cc STP noble gas/cc water. STP stands for standard temperature (0°C) and pressure (760mmHg=l atmosphere). What is the solubility of argon in distilled water at sea level at 15 °C The answer, from Fig. 13.1, is 3.5 x 10 4cc STP Ar/cc water. 

The lack of chemical interactions in the noble gases makes them ideal gases, and as such their solubility in water is directly proportional to their partial pressure in air. This, in turn, depends on the barometric pressure, which is linearly correlated to the altitude. The higher the altitude, the less noble gases dissolve in water. This relation is expressed in Fig. 13.2. The correction factor, read on the right vertical axis in Fig. 13.2, is multiplied by 

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