The total energy of an electron in an atom in an orbit is `-3.4eV`. Its kinetic and potential energies are, respectively:

Options

A. 3.4eV,3.4eV
B. `-3.4eV,-3.4ev`
C. `-3.4eV,-6.8eV`
D. `3.4 eV,-6.8eV`

Explanation

To solve the problem, we need to find the kinetic energy (KE) and potential energy (PE) of an electron in an atom given that the total energy (TE) is -3.4 eV.

### Step-by-Step Solution:

1. **Understanding Total Energy**:
The total energy (TE) of an electron in an orbit is given by the formula:
\[ TE = KE + PE \]
where KE is the kinetic energy and PE is the potential energy.

2. **Using the Relationships**:
For an electron in an atom, there are specific relationships between the total energy, kinetic energy, and potential energy:
- The kinetic energy (KE) is equal to the negative of the total energy:
\[ KE = -TE \]
- The potential energy (PE) is twice the total energy:
\[ PE = 2 \times TE \]

3. **Calculating Kinetic Energy**:
Given that the total energy \( TE = -3.4 \, \text{eV} \):
\[ KE = -(-3.4 \, \text{eV}) = 3.4 \, \text{eV} \]

4. **Calculating Potential Energy**:
Now, we can calculate the potential energy:
\[ PE = 2 \times (-3.4 \, \text{eV}) = -6.8 \, \text{eV} \]

5. **Final Results**:
Thus, the kinetic energy and potential energy of the electron are:
- Kinetic Energy (KE) = \( 3.4 \, \text{eV} \)
- Potential Energy (PE) = \( -6.8 \, \text{eV} \)

### Summary of Results:
- Kinetic Energy (KE) = \( 3.4 \, \text{eV} \)
- Potential Energy (PE) = \( -6.8 \, \text{eV} \)