An atomic number is the number of protons that the atom of a particular element has.
For example, take carbon. Carbon has 6 protons. It's atomic number is 6.
(1) MO₂(s) + C(s) → M(s) + CO₂ (g), ΔG₁ = 288.9 kJ/mol
(2) C(s) + O₂(g) → CO₂(g), ΔG₂ = -394.4 kJ/mol
By adding both equations 1 + 2 we get the coupled reaction:
MO₂(s) + 2 C(s) + O₂(g) → M(s) + 2 CO₂(g)
ΔG⁰ = ΔG₁ + ΔG₂
= 288.9 + (-394.4) = -105.5 kJ/mol = -105500 J/mol
Temperature T = 25 + 273.15 = 298.15 K
Molar gas constant R = 8.314 J/mol.K
K =

=
= 3.05 x 10¹⁸
When you doing a titration, you need to use an indicator to confirm whether the reaction is completed. When the indicator has the color change and will not change back in one minute, the reaction is finished and you don't need to add more.
It will have an overall positive charge.