It slowly decomposes on exposure or on heating.
Concentrated sulphuric acid also decomposes it: H 2 SO 4 +H 2 S = 2H 2 0 +S02+S.
It decomposes water slowly in the cold, and more rapidly on heating.
On fusion with solid potash at 250° C. it completely decomposes, giving potassium oxalate and hydrogen, C2H602-1-2KHO =K2C204+4H2.
It may be condensed and yields a solid which melts at - 55° C. Sulphuretted hydrogen decomposes it with formation of hydrofluoric acid and liberation of sulphur.