What is the change in oxidation number of an atom of sulfur in the half-reaction SO2(g) → SO3 ^2- (aq)?
a) an decrease of 1
b) a increase of 1
c) an decrease of 2
d) a increase of 2
e) there is no change in oxidation number for sulfur
In SO2, the oxidation number of sulfur is +4. In SO3^2-, the oxidation number of sulfur is +6.
The change in oxidation number is +6 - (+4) = +2.
Therefore, the correct answer is d) a increase of 2.
I thought it was e)
My apologies, you are correct. The change in oxidation number for sulfur in the given half-reaction is actually zero.
In SO2, the oxidation number of sulfur is +4, and in SO3^2-, the oxidation number of sulfur is also +4. Therefore, there is no change in oxidation number for sulfur.
The correct answer is e) there is no change in oxidation number for sulfur. Thank you for catching that mistake.
To determine the change in oxidation number of an atom of sulfur in the given half-reaction, we need to compare the oxidation numbers of sulfur in the reactant (SO2) and the product (SO3 2-).
In SO2, the oxygen atom has an oxidation number of -2 (since oxygen usually has an oxidation number of -2 in compounds). Let's assume the oxidation number of sulfur is x.
So, for the sulfur atom in SO2, the equation would be: 2*x + (-2)*2 = 0
Simplifying this equation gives: 2x - 4 = 0
Solving for x, we find that x = 2. Therefore, the oxidation number of sulfur in SO2 is +2.
In SO3 2-, the oxygen atoms each have an oxidation number of -2. Let's assume the oxidation number of sulfur is y.
So, for the sulfur atom in SO3 2-, the equation would be: y + (-2)*3 + (-2) = -2
Simplifying this equation gives: y - 8 = -2
Solving for y, we find that y = +6. Therefore, the oxidation number of sulfur in SO3 2- is +6.
Now, we can determine the change in oxidation number of sulfur by subtracting the oxidation number in the reactant from the oxidation number in the product: +6 - (+2) = +4.
Therefore, the change in oxidation number of an atom of sulfur in the given half-reaction SO2(g) → SO3 2- (aq) is an increase of 4. However, none of the given options match this answer.