The atomic mass and atomic number of lead are 208 and 82. The atomic mass and atomic number of bismuth are 209 and 83. The `"neutron"//"proton"` ratio in an atom

Options

A. Is higher in lead than in bismuth
B. Is lower in lead than in bismuth
C. Is equal in both lead and bismuth
D. None of these

Explanation

To solve the problem of finding the neutron-to-proton (n/p) ratio for lead and bismuth, we can follow these steps:

### Step 1: Identify the atomic mass and atomic number
- For lead (Pb):
- Atomic mass = 208
- Atomic number = 82
- For bismuth (Bi):
- Atomic mass = 209
- Atomic number = 83

### Step 2: Calculate the number of neutrons
The number of neutrons can be calculated using the formula:
\[ \text{Number of Neutrons} = \text{Atomic Mass} - \text{Atomic Number} \]

- For lead:
\[ \text{Number of Neutrons (Pb)} = 208 - 82 = 126 \]

- For bismuth:
\[ \text{Number of Neutrons (Bi)} = 209 - 83 = 126 \]

### Step 3: Calculate the neutron-to-proton ratio (n/p)
The neutron-to-proton ratio can be calculated using the formula:
\[ \text{n/p ratio} = \frac{\text{Number of Neutrons}}{\text{Number of Protons}} \]

- For lead:
\[ \text{n/p ratio (Pb)} = \frac{126}{82} \approx 1.53 \]

- For bismuth:
\[ \text{n/p ratio (Bi)} = \frac{126}{83} \approx 1.51 \]

### Step 4: Compare the n/p ratios
Now we can compare the n/p ratios of lead and bismuth:
- n/p ratio of lead ≈ 1.53
- n/p ratio of bismuth ≈ 1.51

### Conclusion
Since the n/p ratio of lead (1.53) is greater than that of bismuth (1.51), we conclude that the n/p ratio is higher in lead than in bismuth.

### Final Answer
The correct option is: **The n/p ratio is higher in lead than in bismuth.**

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