Protons are held inside nucleous with neutrons with large amount of force. So mere rubbing doesn't help in breaking the nucleous of an atom. But electrons are far from the nucleous and the force of attraction is smaller. So electrons can jump readily while protons can't
The answer is C a combustion’s reaction
Answer is: a) is has increased.
There are two types of reaction:
1) endothermic reaction (chemical reaction that absorbs more energy than it releases).
For example, the breakdown of ozone is an endothermic process. Ozone has lower energy than molecular oxygen (O₂) and oxygen atom, so ozone need energy to break bond between oxygen atoms.
2) exothermic reaction (chemical reaction that releases more energy than it absorbs).
For example, ΔH(reaction) = -225 kJ/mol; this is exothermic reaction.
Hydrogen i suppose is the right one
