Amongst the three isotopes of Neon - `._(10)^(20)Ne,._(10)^(21 )Ne and _(10)^(22)Ne` the nucleus with the lowest n/p ratio is

Options

A. `._(10)^(22)"Ne"`
B. `._(10)^(21)"Ne"`
C. `._(10)^(20)"Ne"`
D. All of these

Answer

To determine which isotope of Neon has the lowest neutron-to-proton (n/p) ratio, we will analyze the three isotopes provided: \( _{10}^{20}\text{Ne} \), \( _{10}^{21}\text{Ne} \), and \( _{10}^{22}\text{Ne} \).

### Step 1: Identify the number of protons and neutrons in each isotope.

- The atomic number of Neon (Ne) is 10, which means all isotopes of Neon have 10 protons.
- The mass number (A) of each isotope indicates the total number of protons and neutrons combined.

For each isotope:
1. **For \( _{10}^{20}\text{Ne} \)**:
- Protons (p) = 10
- Neutrons (n) = Mass number - Protons = 20 - 10 = 10
- n/p ratio = \( \frac{10}{10} = 1 \)

2. **For \( _{10}^{21}\text{Ne} \)**:
- Protons (p) = 10
- Neutrons (n) = Mass number - Protons = 21 - 10 = 11
- n/p ratio = \( \frac{11}{10} = 1.1 \)

3. **For \( _{10}^{22}\text{Ne} \)**:
- Protons (p) = 10
- Neutrons (n) = Mass number - Protons = 22 - 10 = 12
- n/p ratio = \( \frac{12}{10} = 1.2 \)

### Step 2: Compare the n/p ratios.

Now we have the n/p ratios for each isotope:
- \( _{10}^{20}\text{Ne} \): n/p = 1
- \( _{10}^{21}\text{Ne} \): n/p = 1.1
- \( _{10}^{22}\text{Ne} \): n/p = 1.2

### Step 3: Identify the lowest n/p ratio.

From the calculated ratios, we can see that:
- The lowest n/p ratio is for \( _{10}^{20}\text{Ne} \) which is 1.

### Conclusion:

Thus, the nucleus with the lowest n/p ratio among the isotopes of Neon is \( _{10}^{20}\text{Ne} \).

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