Analysis of water in borate glasses

A method capable of fairly accurate determination of the water content (<1 mole%) in borate glasses has been developed. It is based on the principle, that when a glass sample is melted in an evacuated tube, the water leaves the sample thereby producing a water vapour pressure from which the water content of the glass can be calculated. The maximum error is about 20%, but for "higher" values of water content, (i.e. more than 0.25 mole% H2O) it is well below 10%.