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What is the velocity of an electron in the nth energy level of an atom?

1. vₙ = 2πkZe² / nh
2. vₙ = (2.19 × 10⁶ m/s) Z / n
3. vₙ = (2.19 × 10⁶) 2 / 3 (Z = 2 and n = 3)
4. vₙ = 1.46 × 10⁶ m/s

Correct answer: vₙ = (2.19 × 10⁶ m/s) Z / n

Solution

The speed of an electron in the nth orbit of a hydrogen-like atom is given by v = (2.19 × 10⁶ m/s) Z / n, where Z is the atomic number and n is the orbit number. This formula is derived from Bohr's model of the atom.

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