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Given below are two statements. Statement I: According to Bohr's model of an atom, qualitatively the magnitude of velocity of electron increases with decrease in positive charges on the nucleus as there is no strong hold on the electron by the nucleus. Statement II: According to Bohr's model of an atom, qualitatively the magnitude of velocity of electron increases with decrease in principal quantum number. In the light of the above statements, choose the most appropriate answer from the options given below:

1. Both Statement I and Statement II are false
2. Both Statement I and Statement II are true
3. Statement I is false but Statement II is true
4. Statement I is true but Statement II is false

Correct answer: Statement I is false but Statement II is true

Solution

Statement I is incorrect because, according to Bohr's model, the velocity of an electron actually increases with an increase in positive charge from the nucleus, as stronger attraction leads to higher velocity. Statement II is correct since, in Bohr's model, as the principal quantum number decreases, the electron is closer to the nucleus and thus has a higher velocity.

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