What is the total of the oxidation numbers of oxygen atoms in sodium peroxide?
a) +4
b) +2
c) -4
d) -2
e) 0
To determine the oxidation number of oxygen in sodium peroxide, we first need to determine the oxidation numbers for the other elements.
The oxidation number of sodium (Na) is always +1 in its compounds.
The overall charge of the compound sodium peroxide (Na2O2) is 0 because it is a neutral compound.
Let x be the oxidation number of oxygen (O). Since there are two oxygen atoms in sodium peroxide, we can write the following equation:
(2 x oxidation number of O) + (2 x oxidation number of Na) = 0
(2 x) + (2(+1)) = 0
2x + 2 = 0
2x = -2
x = -1
Therefore, the oxidation number of oxygen in sodium peroxide is -1.
The sum of the oxidation numbers of the oxygen atoms in sodium peroxide is (-1) + (-1) = -2.
Therefore, the correct option is d) -2.