Question

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

• A. -5.44 × 10⁻19eV
• B. -5.44 × 10⁻19cal
• C. -5.44 × 10⁻19J
• D. -5.44 × 10⁻19J

Hint:

Energy levels of hydrogen atom vary as: Eₙ ∝ -(1)/(n²)

Answer 1

The Correct Option is C

Step 1: Energy of electron in nᵗh Bohr orbit: Eₙ = -(13.6)/(n²)eV Step 2: For n=2: E₂ = -(13.6)/(4) = -3.4eV Step 3: Convert into joules: 1eV = 1.6 × 10⁻19J E₂ = -3.4 × 1.6 × 10⁻19 = -5.44 × 10⁻19J