a) The opposite of the opposite of 2 is 2. It is located 2 units to the right of 0 on the number line. In the attached, it is the red dot labeled P.
__
b) The opposite of 2 is -2. It is located 2 units to the left of 0 on the number line. In the attached, it is the blue dot. It is not in the same place as point P.
Balanced chemical equations only show formulae, not names. A balancing number, written in normal script, multiplies all the atoms in the substance next to it.
