`K_a` of `H_2O_2` is of the order of

Options

A. `10^(-12)`
B. `10^(-14)`
C. `10^(-16)`
D. `10^(-10)`

Explanation

To determine the \( K_a \) (acid dissociation constant) of hydrogen peroxide (\( H_2O_2 \)), we can follow these steps:

### Step 1: Understand the concept of \( K_a \)
The acid dissociation constant (\( K_a \)) is a measure of the strength of an acid in solution. It quantifies the extent to which an acid can donate protons (\( H^+ \)) to the solution.

### Step 2: Identify the dissociation reaction
For hydrogen peroxide, the dissociation can be represented as:
\[ H_2O_2 \rightleftharpoons H^+ + HO_2^- \]
This shows that when hydrogen peroxide dissociates, it produces hydrogen ions and the peroxide ion.

### Step 3: Write the expression for \( K_a \)
The expression for the acid dissociation constant \( K_a \) is given by:
\[ K_a = \frac{[H^+][HO_2^-]}{[H_2O_2]} \]
Where:
- \([H^+]\) is the concentration of hydrogen ions,
- \([HO_2^-]\) is the concentration of the peroxide ion,
- \([H_2O_2]\) is the concentration of undissociated hydrogen peroxide.

### Step 4: Find the value of \( K_a \)
From the information provided in the video transcript, we know that the \( K_a \) of \( H_2O_2 \) is approximately \( 1.55 \times 10^{-12} \).

### Step 5: Conclude the order of \( K_a \)
Thus, we can conclude that the \( K_a \) of \( H_2O_2 \) is of the order of \( 10^{-12} \).

### Final Answer
The \( K_a \) of \( H_2O_2 \) is of the order of \( 10^{-12} \).

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