NEET Practice Questions (MCQs) with Answers & Solutions

In the hydrogen atom, the energy required for electronic transitions increases as the difference between the initial and final principal quantum numbers increases. The transition from n=1 to n=2 corresponds to the largest energy gap (Lyman series) and therefore requires the greatest amount of energy to be absorbed by the hydrogen atom.

$ E_n = { -13.6 Z^2 \over n ^2 } eV atom ^ {-1} $ For hydrogen atom in ground state Z=1 and n=1 for $ Be^{+3} $ ion in first excited state Z= 4 and n= 2

When sodium chloride is introduced into a Bunsen flame, the heat energy is absorbed by the sodium atoms, promoting their electrons to higher energy levels. As the excited electrons return to their ground state, they emit excess energy as radiation in the visible region, specifically a yellow color.

The statement that the exact path of an electron in a 2p orbital cannot be determined is based on the Heisenberg Uncertainty Principle. This principle states that it is impossible to simultaneously determine the exact position and momentum (or velocity) of a particle with absolute precision.

The maximum number of electrons in a subshell is given by the expression 4l + 2, where l is the azimuthal quantum number. This is known as the 'Pauli Exclusion Principle', which states that no two electrons in an atom can have the same set of four quantum numbers.