Question

A teacher does a demonstration for her science class. She has two samples of white powder that look the same. She also has two beakers that are each filled with the same amount of water. She adds powder X to the first beaker and adds powder Y to the second beaker. The first beaker becomes cold to the touch. The second beaker does not experience a significant change in temperature.Which of the following does this provide evidence for?'

Answer 1

There is a temperature change in the surroundings of the apparatus for X, which is commonly considered a sign of a ____________(reaction or no reaction)

Take notice of the word I underlined, because the temperature is also changed in phase changes. Here there is HEAT because there is an endothermic ____________.