How to tell if a reaction is exothermic.

In chemistry, the type of an atom (what element it is) is determined by: a) the number of protons it contains in its nucleus.b) the number of neutrons it contains in its nucleus.c) the number of protons it has in a cloud around the nucleus.d) the number of neutrons it has in a cloud around the nucleus.e) the number of electrons it exchanges with its neighbors.

When hydrogen peroxide (h2o2) is added to potassium iodide (ki) solution, the hydrogen peroxide decomposes into water (h2o) and oxygen (o2). the chemical equation for the decomposition reaction is: 2h2o2—> 2h2o + o2. what is the role of the potassium iodide in this reaction? a. reactant. b. product. c. precipitate. d. catalyst.

Which of these natural resources is non-renewable a.corn b.wind c.geothermal d.natural gas