Uranium ultimately decays into a stable isotope of

Options

A. Radium
B. Carbon
C. Lead
D. Neptunium

Explanation

To determine the stable isotope that uranium ultimately decays into, we will analyze the decay process of uranium step by step.

### Step-by-Step Solution:

1. **Understanding Uranium Decay**:
- Uranium is a radioactive element that undergoes a series of decay processes. The most common isotopes of uranium are Uranium-238 and Uranium-235.

2. **Decay Series**:
- Uranium-238 decays through a series of alpha and beta decays. This decay series includes several intermediate isotopes before reaching a stable end product.
- The decay chain of Uranium-238 leads to a series of elements, including radium and radon, before finally reaching a stable isotope.

3. **Identifying the Final Stable Isotope**:
- The final stable isotope produced from the decay of Uranium-238 is Lead-206 (Pb-206).
- Similarly, Uranium-235 decays to Lead-207 (Pb-207) after a series of decay steps.

4. **Evaluating the Options**:
- The question provides several options: Uranium, Carbon, Lead, and Neptunium.
- Uranium cannot be the final product since it is the starting material.
- Carbon is a stable element but is not the final product of uranium decay.
- Neptunium is also radioactive and cannot be the stable end product.
- Lead, specifically Lead-206 or Lead-207, is the stable isotope that uranium ultimately decays into.

5. **Conclusion**:
- Therefore, the correct answer is that uranium ultimately decays into a stable isotope of Lead.

### Final Answer:
Uranium ultimately decays into a stable isotope of **Lead**.

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