The negative value of packing fraction indicates that the isotope is

Options

A. Unstable
B. Very stable
C. Artifical
D. Stable

Answer

To determine what a negative value of packing fraction indicates about an isotope, we can follow these steps:

### Step 1: Understand Packing Fraction
The packing fraction is defined as the ratio of the mass of a nucleus to its mass number (A). It is calculated using the formula:
\[ \text{Packing Fraction} = \frac{\text{Mass of nucleus}}{A} \]
A positive packing fraction indicates that the mass of the nucleus is greater than the mass number, while a negative packing fraction indicates the opposite.

### Step 2: Analyze the Implications of Packing Fraction
A negative packing fraction suggests that the mass of the nucleus is less than the mass number. This typically implies that the nucleus is more tightly bound, which is associated with greater stability.

### Step 3: Relate Packing Fraction to Nuclear Stability
The stability of a nucleus is inversely proportional to the packing fraction. This means:
- A high packing fraction (positive value) corresponds to a less stable nucleus.
- A low or negative packing fraction indicates a more stable nucleus.

### Step 4: Conclusion
Therefore, if the packing fraction is negative, it indicates that the isotope is stable.

### Final Answer
The negative value of packing fraction indicates that the isotope is stable.

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