Answer:- oxygen.
Explanations:- The electronic configuration is given and we are asked to figure out the electrically neutral atom that will have the electron configuration, 
.
The sum of electrons for this electron configuration is 8. If we look at the periodic table then 8 is the atomic number of oxygen.
So, the electrically neutral atom for the given electron configuration is oxygen.
A) Magnesium + Chlorine -> Magnesium chloride ( Mg + Cl2 -> MgCl2)
b) Potassium + Oxygen -> Potassium oxide
( 2K + O2 -> K2O )
c) Sodium + Bromine -> Sodium bromide
( 2Na + Br2 -> 2NaBr)
d) Carbon + Oxygen -> Carbon dioxide
( C + O2 -> CO2 ) This reaction occurs when heated.
<span>2C2H6 + 7O2 = 4CO2 + 6H2O
</span>
According to the equation of the reaction of ethane combustion, ethane and carbon dioxide have following stoichiometric ratio:
n(C2H6) : n(CO2) = 1 : 2
n(CO2) = 2 x n(C2H6)
n(CO2) = 2 x 5.2 = 10.4 mole of CO2 is formed
