In carbon-nitrogen nuclear fusion cycle, protons are fused to form a helium nucleus, positrons and release some energy. The number of protons fused and the number of positrons released in this process respectively are

Options

A. 4,4
B. 4,2
C. 2,4
D. 4,6

Answer

To solve the question regarding the carbon-nitrogen nuclear fusion cycle, we need to analyze the process of fusion that occurs in this cycle. Here’s a step-by-step breakdown of the solution:

### Step 1: Understanding the Fusion Process
In the carbon-nitrogen cycle, protons (which are hydrogen nuclei) undergo fusion to form helium. The process involves the combination of multiple protons.

**Hint:** Remember that fusion processes often involve the combination of lighter elements to form heavier ones, releasing energy in the process.

### Step 2: Identifying the Number of Protons
From the carbon-nitrogen cycle, it is known that 4 protons are required to ultimately produce one helium nucleus. This can be represented as:
\[ 4 \, ^1H \rightarrow ^4He \]

**Hint:** Look for the conservation of nucleons in fusion reactions; the total number of protons before and after the reaction must balance.

### Step 3: Identifying the Number of Positrons
In addition to forming helium, the fusion process also releases positrons. In the carbon-nitrogen cycle, for every 4 protons fused, 2 positrons are emitted. This can be summarized as:
\[ 4 \, ^1H \rightarrow ^4He + 2 \, e^+ + \text{energy} \]

**Hint:** Pay attention to the byproducts of fusion reactions; they often include particles like positrons and neutrinos.

### Step 4: Conclusion
From the analysis, we can conclude that during the carbon-nitrogen fusion cycle:
- The number of protons fused is **4**.
- The number of positrons released is **2**.

Thus, the answer to the question is:
- Number of protons fused: **4**
- Number of positrons released: **2**

### Final Answer
The number of protons fused and the number of positrons released in this process respectively are **4 and 2**.

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