The sum of protons, electrons and neutrons in the heaviest isotope of hydrogen is

Options

A. 3
B. 5
C. 4
D. 6

Answer

To find the sum of protons, electrons, and neutrons in the heaviest isotope of hydrogen, we will follow these steps:

### Step 1: Identify the isotopes of hydrogen
Hydrogen has three isotopes:
1. **Protium (¹H)** - Mass number 1 (1 proton, 0 neutrons)
2. **Deuterium (²H)** - Mass number 2 (1 proton, 1 neutron)
3. **Tritium (³H)** - Mass number 3 (1 proton, 2 neutrons)

### Step 2: Determine the heaviest isotope
Among these isotopes, Tritium (³H) is the heaviest because it has the highest mass number (3).

### Step 3: Identify the number of protons, electrons, and neutrons in Tritium
- **Protons**: The atomic number of Tritium is 1, which means it has 1 proton.
- **Electrons**: In a neutral atom, the number of electrons equals the number of protons. Therefore, Tritium has 1 electron.
- **Neutrons**: The number of neutrons can be calculated using the formula:
\[ \text{Neutrons} = \text{Mass number} - \text{Protons} \]
For Tritium:
\[ \text{Neutrons} = 3 - 1 = 2 \]

### Step 4: Calculate the sum of protons, electrons, and neutrons
Now, we can sum the number of protons, electrons, and neutrons:
\[ \text{Sum} = \text{Protons} + \text{Electrons} + \text{Neutrons} \]
Substituting the values:
\[ \text{Sum} = 1 + 1 + 2 = 4 \]

### Final Answer
The sum of protons, electrons, and neutrons in the heaviest isotope of hydrogen (Tritium) is **4**.

---