A typical cold pack involves mixing a solid salt, such as ammonium nitrate, with water. In other words, the cold pack you might buy at a pharmacy to put on a sprained ankle is just a dissolution chemical reaction. This reaction must be:: a. Exothermic and spontaneous
b. Endothermic and spontaneous
с. Endothermic requiring work
d. Exothermic requiring work
e. Not enough information

Does the energy in a solid increase or decrease when changing to a liquid?

How many mmols of tris-hcl are there in 100 ml of a 100 mm tris-hcl buffer solution at ph 8.1? note that the 100 mm refers to the sum of tris and tris-hcl concentrations?

The characteristics of two different types of reactions are shown below: reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of an element. which statement is true about the atoms of the elements that participate in the two reactions? their identity changes in both reaction a and reaction b. their identity changes in reaction a but not in reaction b. their identity changes in reaction b but not in reaction a. their identity remains the same in both reaction a and reaction b.