Answer:
Potassium (K) = (2,8,8,1)
This is the element that has three(3) filled energy level and one valence electron
The element that is most reactive to gas is Hydrogen
An atom is the smallest you can get to identify the element.
An exothermic reaction releases heat. An endothermic reaction absorbs heat. Burning gas releases heat so it would be exothermic. Acid and water react heating the beaker would be exothermic because it releases heat from the reaction. Hope this helps! ;)
The chemical properties, chemical reactivity
