41 replies to this topic

[sydad]

Hi again waruna,

I would not take too much notice of "expiry" dates on inorganic chemicals. As a general rule, if kept in a sealed, waterproof container, they may be regarded as almost completely stable: that is to say that they undergo no changes at all over time. Expiry dates are compulsory on foods and many other products, but really often mean very little. I remember seeing expiry dates on sodium chloride (common salt), which is probably the most stable substance known, and calcium sulphate is probably equally stable.

Syd.

[waruna]

Hello Sydad, thanks for the info mate