Question

which of the following is not an observable or measurable outcome for an exothermic reaction? the temperature of the water in the beaker goes down. the temperature of the beaker itself increases. the temperature of the water in the beaker goes up. light is emitted from the beaker.

Explanation:

An exothermic reaction releases energy (usually as heat, sometimes light). So, the temperature of the surroundings (like water in the beaker or the beaker itself) should increase, and light can be emitted (e.g., combustion). A decrease in water temperature would happen in an endothermic reaction (which absorbs heat), so it's not an observable outcome for an exothermic reaction.

Answer:

The temperature of the water in the beaker goes down.