Question

What is the oxidation number of carbon in K\(_2\)C\(_2\)O\(_4\)?

• A. –2
• B. +3
• C. 0
• D. +4

Hint:

Always use the rule: sum of oxidation states in a neutral compound is zero.

Answer 1

The Correct Option is B

Step 1: Write oxidation states of known elements.
Potassium (K) has oxidation state +1.
Oxygen (O) has oxidation state –2.
Step 2: Let oxidation state of carbon be \(x\).
\[ 2(+1) + 2x + 4(-2) = 0 \]
Step 3: Solve the equation.
\[ 2 + 2x - 8 = 0 \Rightarrow 2x = 6 \Rightarrow x = +3 \]
Step 4: Conclusion.
The oxidation number of carbon is +3.