Q value of a nuclear reactions is positive . The reaction is

Options

A. Exothermic
B. Endothermic
C. Elastic
D. Both exothermic and endothermic

Answer

To determine the nature of a nuclear reaction when the Q value is positive, we can follow these steps:

### Step 1: Understand the Q Value
The Q value of a nuclear reaction is defined as the difference in energy between the products and the reactants. Mathematically, it can be expressed as:
\[ Q = E_{\text{products}} - E_{\text{reactants}} \]

### Step 2: Analyze the Sign of Q Value
If the Q value is positive, it indicates that the energy of the products is greater than the energy of the reactants:
\[ Q > 0 \]
This means that energy is released during the reaction.

### Step 3: Identify the Type of Reaction
A positive Q value signifies that the reaction is exothermic. In an exothermic reaction, energy is released to the surroundings, typically in the form of heat or radiation.

### Step 4: Contrast with Endothermic Reactions
In contrast, if the Q value were negative (i.e., \( Q < 0 \)), it would indicate that the reaction is endothermic, meaning that energy is absorbed from the surroundings to proceed with the reaction.

### Conclusion
Since the Q value is positive, the reaction is classified as an exothermic reaction.

### Final Answer
The reaction is exothermic.

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