I think the answer is hmmm I think
Answer: Mendeleev improve newlands periodic table because he swapped the order of some elements if that fitted their properties better.
Explanation: I hope this helps!... :)
The answer is (2).
Both the proton and the neutron have masses around 1amu.
In order to balance the chemical equation, you need to make sure the number of atoms of each element on the reactant side is equal to the number of atoms of each element on the product side. In order make both sides equal, you will need to multiply the number of atoms in each element until both sides are equal
