The combustion of Li, Na, K in excess of air gives major oxides

Options

A. `Li_2O, Na_2O_2, KO_2`
B. `Li_2O_2, Na_2O, K_2O`
C. `Li_2O, NaO_2, KO_2`
D. `LiO_2, Na_2O_2, K_2O_2`

Answer

To solve the question regarding the combustion of lithium (Li), sodium (Na), and potassium (K) in excess air and the major oxides produced, we can follow these steps:

### Step 1: Understand the Reaction
When lithium, sodium, and potassium are burned in excess air, they react with oxygen to form oxides. The type of oxide formed depends on the metal and the conditions of the reaction.

### Step 2: Identify the Major Oxides
- **Lithium (Li)**: When lithium combusts in excess air, it primarily forms lithium oxide (Li₂O).
- **Sodium (Na)**: Sodium reacts with oxygen to form sodium peroxide (Na₂O₂) when there is an excess of air.
- **Potassium (K)**: Potassium, when burned in excess air, forms potassium superoxide (KO₂).

### Step 3: Summarize the Major Oxides
Thus, the major oxides formed from the combustion of these alkali metals in excess air are:
- Lithium (Li) → Lithium oxide (Li₂O)
- Sodium (Na) → Sodium peroxide (Na₂O₂)
- Potassium (K) → Potassium superoxide (KO₂)

### Step 4: Conclusion
The major oxides formed during the combustion of lithium, sodium, and potassium in excess air are:
- Li₂O for lithium
- Na₂O₂ for sodium
- KO₂ for potassium

### Final Answer
The major oxides formed are:
- Li₂O (Lithium oxide)
- Na₂O₂ (Sodium peroxide)
- KO₂ (Potassium superoxide)