Calculate the oxidation number of Mn in MnO 2 .
Calculate the oxidation number of Mn in MnO2 .
- A) 6
- B) 4
- C) 2
- D) 8
Correct Answer: B) 4
Explanation
The oxidation number of an element in a compound represents the charge that the element would have if all the shared electrons were assigned to the element with a greater attraction for electrons. To determine the oxidation number of Mn in MnO\(_2\), we can use the following steps:
1. Assign oxidation numbers to the known elements in the compound. In this case, we know that oxygen has an oxidation number of -2 (unless it's in a peroxide or a superoxide, but those are not the cases here).
2. Use the oxidation numbers of the known elements and the fact that the sum of the oxidation numbers in a neutral compound equals zero to determine the oxidation number of the unknown element (Mn in this case).
Let x be the oxidation number of Mn. We have:
\[ x + 2(-2) = 0 \]3. Solve the equation for x:
\[ x - 4 = 0 \\ x = 4 \]
So, the oxidation number of Mn in MnO\(_2\) is 4, which corresponds to Option B.