Determine total number of neutrons in three isotopes of hydrogen.

Options

A. 1
B. 2
C. 3
D. 4

Explanation

To determine the total number of neutrons in the three isotopes of hydrogen, we first need to identify the isotopes and their respective mass numbers and atomic numbers.

### Step 1: Identify the isotopes of hydrogen
Hydrogen has three isotopes:
1. Protium (¹H) - Mass number (A) = 1, Atomic number (Z) = 1
2. Deuterium (²H) - Mass number (A) = 2, Atomic number (Z) = 1
3. Tritium (³H) - Mass number (A) = 3, Atomic number (Z) = 1

### Step 2: Calculate the number of neutrons for each isotope
The number of neutrons (N) in an isotope can be calculated using the formula:
\[ N = A - Z \]
Where:
- N = Number of neutrons
- A = Mass number
- Z = Atomic number

#### For Protium (¹H):
- A = 1, Z = 1
\[ N = 1 - 1 = 0 \]
So, Protium has 0 neutrons.

#### For Deuterium (²H):
- A = 2, Z = 1
\[ N = 2 - 1 = 1 \]
So, Deuterium has 1 neutron.

#### For Tritium (³H):
- A = 3, Z = 1
\[ N = 3 - 1 = 2 \]
So, Tritium has 2 neutrons.

### Step 3: Calculate the total number of neutrons
Now, we sum the number of neutrons from each isotope:
\[ \text{Total neutrons} = N_{Protium} + N_{Deuterium} + N_{Tritium} \]
\[ \text{Total neutrons} = 0 + 1 + 2 = 3 \]

### Conclusion
The total number of neutrons in the three isotopes of hydrogen is **3**.

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