In physics and chemical engineering, the term Pouillet effect refers to an exothermic reaction that takes place when a liquid is added to a powder.
Strictly speaking, the heat generated is caused by adhesion of the liquid to the surface of the particles rather than by a chemical reaction.
[1] It was first observed in 1802 by physicist John Leslie, who noted that heat was evolved when dry sawdust was wetted with water.
[5] Joseph Mellor argued that this is due to the negative thermal expansion coefficient of water between 0 and 4 degrees Celsius,[6] with the temperature change
According to this formula, any liquid with a negative thermal expansion coefficient would be expected to exhibit a drop in temperature.