Solution
Step 1: Total energy relation
For hydrogen atom:
Total Energy (E) = − Kinetic Energy (K.E.)
⇒ K.E. = −E
Step 2: First excited state
First excited state ⇒ n = 2
Given:
E = −3.4 eV
Step 3: Calculate kinetic energy
K.E. = − (−3.4)
K.E. = 3.4 eV
Step 4: Convert into required form
3.4 eV = 34 × 10−1 eV
Final Answer = 34