Electron Configuration | MCQs

Explanation

• Group IIIA (or group 13) elements, such as boron (B), aluminum (Al), and gallium (Ga), lose three electrons to form ions with a charge of +3.
• This means that they typically form compounds by losing three electrons, resulting in a valency of +3.

Explanation

• Transition elements, also known as transition metals, are a group of elements in the d-block of the periodic table.
• They are characterized by their ability to form ions with different charges.
• They are often found in the middle of the periodic table.

Explanation

• As you move down a group in the periodic table, the atomic size increases.
• This means that the outermost electrons are farther away from the nucleus, making it easier for the atom to gain an extra electron.
• As a result, the electron affinity decreases down a group.

Explanation

• Henry Moseley's famous work in 1913 showed that the chemical properties of elements are a periodic function of their atomic number (Z), not their atomic mass.
• This discovery led to the modern periodic table, where elements are arranged in order of increasing atomic number (Z), rather than atomic mass.

Explanation

The elements in group VIIA of the periodic table are called halogens.

This group consists of the following elements:

• Fluorine (F)
• Chlorine (Cl)
• Bromine (Br)
• Iodine (I)
• Astatine (At)
• Tennessine (Ts)

Explanation

The L shell, also known as the second electron shell, has 02 subshells:

The L shell contains two subshells - 2s, 2p.

The M shell contains three subshells - 3s, 3p, 3d.

The N shell contains four subshells - 4s, 4p, 4d, 4f

Explanation

The K orbit, also known as the first electron shell.

• It can hold a maximum of 2 electrons.

The L orbit, also known as the second electron shell.

• It can hold a maximum of 8 electrons.

The M orbit, also known as the third electron shell.

• It can hold a maximum of 18 electrons.

Explanation

• The formula 2n^2 helps in determining the maximum number of electrons present in an orbit, where n is the principal quantum number (energy level).
• This formula is based on the Aufbau principle and the Pauli exclusion principle, which describe how electrons occupy energy levels in an atom.