CH4 + 2O2 =======> CO2 + 2H2O
The reason people describe water as a universal solvent is because it dissolves almost anything.
It does<span>, however, change the </span>mass<span> of the nucleus. </span>Adding<span> or removing </span>neutrons<span>from the nucleus are how isotopes are created. Protons carry a positive electrical charge and they alone determine the charge of the nucleus.</span>
The answer to your proposed question is Neutron. This is because the atomic mass unit of a neutron is 1 and so it would contribute to the overall mass of the atom.
I hope this answer helped you!