Which of the following is true during an exothermic reaction? heat is created. heat is released. heat is destroyed. heat is absorbed. need as fat as u people can me

Awhite powder is added to a solution. the images show observations made before the powder is added, just after the powder has been added, and a little while later. (the liquid in the small beaker is phenol red solution.) what evidence shows that a chemical change has taken place?