Atomic Structure

Paramagnetic atoms have unpaired electrons. In this case, K, C, and Fe are paramagnetic.

The energy emitted when an electron transitions between two energy levels is proportional to the difference in energy levels.
The larger the difference in energy between the two levels, the greater the energy emitted.
The transition involves a large energy difference compared to the others, resulting in the maximum energy emission.

Thus, the correct answer is (c).

The electron configuration for the element with atomic number Z = 17 (Chlorine) is: The unpaired electron in the 3p orbital has the following quantum numbers: - Principal quantum number (since it is in the third shell) - Azimuthal quantum number (since it is in a p orbital) - Magnetic quantum number (can take values between and ) - Spin quantum number (the electron has a half-spin) Thus, the correct set of quantum numbers is (a).

The energy required to excite the electron can be calculated using the ionisation enthalpy and the relation: Converting this into J: Thus, the correct answer is (d) 9.86.

An electron with a principal quantum number of 2 will be in a higher energy state compared to an electron with a principal quantum number of 1. This is because higher quantum numbers correspond to higher energy levels in an atom.