The energy of the electron in the ground state of hydrogen atom is `-13.6 eV`. Find the kinetic energy of electron in this state.

Options

A. 1.85 eV
B. 13.6 eV
C. 6.8 eV
D. 3.4 eV

Explanation

To find the kinetic energy of the electron in the ground state of a hydrogen atom, we can use the relationship between the total energy (E), kinetic energy (K.E.), and potential energy (P.E.) in a hydrogen atom.

### Step-by-Step Solution:

1. **Understand the Energy Relationships**:
In a hydrogen atom, the total energy (E) is related to the kinetic energy (K.E.) and potential energy (P.E.) as follows:
\[ E = K.E. + P.E. \]
Additionally, for a hydrogen atom:
\[ P.E. = 2 \times E \]
and
\[ K.E. = -E \]

2. **Given Data**:
The total energy of the electron in the ground state of the hydrogen atom is given as:
\[ E = -13.6 \, \text{eV} \]

3. **Calculate the Kinetic Energy**:
Using the relationship \( K.E. = -E \):
\[ K.E. = -(-13.6 \, \text{eV}) = 13.6 \, \text{eV} \]

4. **Conclusion**:
The kinetic energy of the electron in the ground state of the hydrogen atom is:
\[ K.E. = 13.6 \, \text{eV} \]

5. **Select the Correct Option**:
From the options provided, the correct answer is:
- Option 2: 13.6 eV.