Chemistry MCQs for NEET — Practice Questions with Answers

The azimuthal quantum number (l) determines the value of the magnetic quantum number (m_l) which can range from -l to +l. For l = 2, the possible values of m_l are -2, -1, 0, 1, and 2. Therefore, the value of 3 for m_l is not permissible.

Mesons are fundamental particles composed of a quark and an antiquark. They are responsible for the strong nuclear force that binds protons and neutrons together in the nucleus, keeping the nucleons together.

The positron is the antiparticle of the electron, having the same mass as an electron but with a positive charge. It has the same mass as an electron, which is much less than the masses of a neutron, alpha particle, or proton.

The principal quantum number (n) represents the main shell, and the azimuthal quantum number (l) represents the subshell within that main shell. For (n + l) = 8, the possible combinations are: n = 8, l = 0 (s subshell), which can hold 2 electrons, and n = 7, l = 1 (p subshell), which can hold 6 electrons. Together, these can accommodate 2 + 6 = 8 electrons for an atom with atomic number 105.

The line spectrum of two elements is not identical because they have different energy level schemes. The electrons in different elements have different energy levels, and transitions between these levels result in the emission or absorption of specific wavelengths of light, giving rise to unique line spectra.

Bohr's atomic model can explain the spectrum of atoms or ions which are uni-electron species, such as hydrogen atoms, singly ionized helium (He⁺), or doubly ionized lithium (Li²⁺). The model is limited to systems with only one electron orbiting the nucleus.

The given atom has 2 K-shell electrons (1s), 8 L-shell electrons (2s and 2p), 11 M-shell electrons (3s, 3p, and 3d), and 2 N-shell electrons (4s). The total number of s-electrons, which have the spherical distribution, is 2 (1s) + 2 (2s) + 2 (3s) + 2 (4s) = 8.