Question

The energy of an electron in second Bohr orbit of hydrogen atom is:

• A. \(-5.44 \times 10^{-19}\,\text{eV}\)
• B. \(-5.44 \times 10^{-19}\,\text{cal}\)
• C. \(-5.44 \times 10^{-19}\,\text{kJ}\)
• D. -5.44 × 10⁻19J

Hint:

Energy levels in hydrogen vary as 1/n².

Answer 1

The Correct Option is D

Step 1: Energy of electron in hydrogen atom: Eₙ = -(13.6)/(n²)eV
Step 2: For n=2: E = -(13.6)/(4) = -3.4eV
Step 3: Converting to joules: E = -3.4 × 1.6×10⁻19 = -5.44×10⁻19J