Which of the following statement is not true about the following decomposition reaction?`2KClO_3rarr2KCl+3O_2`

Options

A. potassium is undergoing oxidation
B. chlorine is undergoing oxidation
C. oxygen is reduced
D. all of these

Answer

To determine which statement is not true about the decomposition reaction \(2KClO_3 \rightarrow 2KCl + 3O_2\), we need to analyze the oxidation states of the elements involved in the reaction.

### Step-by-Step Solution:

1. **Identify the Reactants and Products:**
- Reactants: \(KClO_3\) (potassium chlorate)
- Products: \(KCl\) (potassium chloride) and \(O_2\) (oxygen gas)

2. **Assign Oxidation States:**
- In \(KClO_3\):
- Potassium (K) has an oxidation state of +1.
- Chlorine (Cl) can be calculated as follows:
- Let the oxidation state of Cl be \(x\).
- The overall charge of \(KClO_3\) is 0.
- The oxidation states of oxygen (O) are -2 (3 oxygen atoms contribute -6).
- Thus, the equation is:
\[ +1 + x + (-6) = 0 \implies x = +5 \]
- Therefore, in \(KClO_3\), K is +1, Cl is +5, and O is -2.

- In \(KCl\):
- K is +1 and Cl is -1.

- In \(O_2\):
- O is 0 (as it is in its elemental form).

3. **Determine Changes in Oxidation States:**
- For potassium (K):
- It remains +1 in both \(KClO_3\) and \(KCl\). No change, hence no oxidation or reduction.
- For chlorine (Cl):
- Changes from +5 in \(KClO_3\) to -1 in \(KCl\). This indicates a gain of electrons (reduction).
- For oxygen (O):
- Changes from -2 in \(KClO_3\) to 0 in \(O_2\). This indicates a loss of electrons (oxidation).

4. **Evaluate the Statements:**
- **Statement 1:** Potassium is undergoing oxidation. (False, as its oxidation state does not change)
- **Statement 2:** Chlorine is undergoing oxidation. (False, as it is undergoing reduction)
- **Statement 3:** Oxygen is getting reduced. (False, as it is undergoing oxidation)
- **Statement 4:** All of the above statements are false. (True)

5. **Conclusion:**
- The statement that is not true about the decomposition reaction is that potassium is undergoing oxidation.