Answer 1)

+

----> 2 HCl
This is a pure
chemical reaction that is taking place.
In this reaction the two chemical species which are Chlorine and Hydrogen undergo addition reaction and form two moles of hydrochloric acid. No new species is formed except the combination of reactants which gives the product.
Answer 2) H + H ----> He + n
This is a nuclear reaction.
As the reactant species is undergoing a reaction which is resulting in formation of new species completely different than the elements in reactants.
Also there is a neutron which is generated after the reaction this is clear indication of nuclear fusion reaction. Hence, it can be called as nuclear reaction.
B.The potential energy the reactants have stored in molecular bonds
Answer:
308,4796 g.
Explanation:
1 mol equals to 107,86 g, now times 2,86 mol, 308,4796 g.
A chemical reaction involves the rearranging of atoms of the same or different elements to form new substances. It is represented by a chemical equation in which the reactants (substances that are broken apart) are written on the left and the products (new substances formed) are written on the right. If more than one reactant or product is needed, they are separated with a + sign. An arrow is used to separate the reactant side of the equation from the product side.
For an atom to be neutral the protons and the electrons should be equal.
Therefore the number of protons are 5
So A is the answer.