Which oxide is formed when potassium is heated in e3xcess of oxygen?

Options

A. `K_(2)O`
B. `KO`
C. `K_(2)O_(2)`
D. `KO_(2)`

Answer

To determine which oxide is formed when potassium (K) is heated in excess of oxygen (O2), we can follow these steps:

### Step 1: Understand the Reaction Conditions
When potassium is heated in the presence of excess oxygen, it can react to form different types of oxides depending on the conditions of the reaction.

**Hint:** Consider the state of the reactants and the amount of oxygen available during the reaction.

### Step 2: Identify Possible Oxides
Potassium can form several oxides:
- Potassium oxide (K2O)
- Potassium peroxide (K2O2)
- Potassium superoxide (KO2)

**Hint:** Think about the oxidation states of potassium and oxygen in these compounds.

### Step 3: Analyze the Reaction with Excess Oxygen
When potassium is heated in excess oxygen, the formation of superoxide (KO2) is favored. This is because superoxides are typically formed when alkali metals react with a large amount of oxygen.

**Hint:** Recall that superoxides are formed when there is a high availability of oxygen.

### Step 4: Write the Reaction
The reaction can be represented as:
\[ 4K + O2 \rightarrow 2K2O2 \] (at lower temperatures)
\[ 4K + O2 \rightarrow 4KO2 \] (at higher temperatures)

**Hint:** Consider the temperature conditions that influence the formation of different oxides.

### Step 5: Conclusion
In the case of heating potassium in excess of oxygen, the primary oxide formed is potassium superoxide (KO2).

**Final Answer:** The oxide formed when potassium is heated in excess of oxygen is potassium superoxide (KO2).

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