sulphuric acid

[solera]

I recall that the freezing point of SA varies with the specific gravity, what is the term used to describe a material of this type, hunting on the net I came up with this detail, Technical grade 93.19% FP of -29.5 degrees C 98/99% grade -1.1 degrees C I seem to remember that on a graph the curve crossed and recrossed.

[Gef]

I don't know what term is used to describe the material but freezing point depression is a colligative property. The freezing point of a solution of sulphuric acid is lower than the freezing points of the pure substances.