Which of the following curve represent zero order reaction of `A rarr` products ?

Options

A.
B.
C.
D.

Explanation

To determine which curve represents a zero-order reaction for the reaction \( A \rightarrow \text{products} \), we can follow these steps:

### Step 1: Understand Zero-Order Reactions
In a zero-order reaction, the rate of reaction is constant and does not depend on the concentration of the reactant. The rate law can be expressed as:
\[ R = k \]
where \( R \) is the rate of reaction and \( k \) is the rate constant.

### Step 2: Derive the Concentration Equation
For a zero-order reaction, the change in concentration of \( A \) over time can be described by the equation:
\[ [A] = [A_0] - kt \]
where:
- \([A]\) is the concentration of \( A \) at time \( t \),
- \([A_0]\) is the initial concentration of \( A \),
- \( k \) is the rate constant,
- \( t \) is time.

### Step 3: Identify the Graph Characteristics
The equation \([A] = [A_0] - kt\) can be rearranged to resemble the equation of a straight line:
\[ y = mx + c \]
where:
- \( y \) is \([A]\),
- \( m \) (the slope) is \(-k\) (which is negative),
- \( x \) is \( t \),
- \( c \) (the y-intercept) is \([A_0]\).

### Step 4: Analyze the Graph
From the characteristics of the graph:
- The graph of a zero-order reaction will be a straight line with a negative slope.
- The y-intercept of the graph will be equal to the initial concentration \([A_0]\).

### Step 5: Choose the Correct Curve
Given the options, we need to find the graph that:
- Is a straight line,
- Has a negative slope,
- Intersects the y-axis at \([A_0]\).

After analyzing the provided curves, the correct curve that represents a zero-order reaction is the one that meets all these criteria.

### Final Answer
The correct curve representing a zero-order reaction of \( A \rightarrow \text{products} \) is option D.

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