Problem 22 - A Complete Resource Book in Chemistry for JEE Main

Question

How many electrons can be accommodated in a p-orbital? (a) 6 electrons (b) 2 electrons (c) 4 electrons (d) none of these

Step-by-Step Solution

Answer

6 electrons can be accommodated in a p-orbital.

Step 1: Understanding the Concept of Orbitals

First, we need to understand that orbitals are regions within an atom where electrons are likely to be found. Electrons in an atom occupy orbitals starting from the lower energy levels.

Step 2: Characteristics of a P-Orbital

P-orbitals have a distinctive shape that resembles a dumbbell and each individual p subshell can hold a maximum of 3 orbitals. Each orbital can hold a maximum of 2 electrons.

Step 3: Total Capacity of a P Subshell

Each p subshell, therefore, comprises three orbitals, and since each orbital can hold 2 electrons, the total number of electrons a full p subshell can accommodate is calculated by multiplying the number of orbitals by electrons per orbital: 3 orbitals * 2 electrons per orbital = 6 electrons.

Key Concepts

Electron Configuration

Electron configuration refers to the arrangement of electrons within an atom's orbitals. This arrangement is crucial because it determines the atom's chemical properties and behavior. Electrons are filled into orbitals following specific rules, with the most fundamental being the Aufbau principle, which states that electrons occupy the lowest energy orbitals first before filling higher ones. Additionally:

• The Pauli Exclusion Principle stipulates that no two electrons in an atom can have the same set of four quantum numbers.
• Hund's Rule indicates that electrons will fill empty orbitals singly before they start pairing up in orbitals within the same subshell.

Understanding electron configuration helps explain elements' positions on the periodic table, particularly the element's outer shell, or valence electrons, which dictate how an element will react with others. Hence, when considering a p-orbital, recognize its contribution as part of the p subshell, which plays a key role in determining chemical bonding and element reactivity.

Orbitals

Orbitals are vital components of the atomic structure, acting as the regions around an atom's nucleus where electrons are likely to be found. Each type of orbital has a unique shape that affects where these electrons can reside, governed by quantum mechanics principles. The main orbital types you’ll encounter include:

• s-orbitals: Spherical in shape, each s subshell contains only one s orbital, capable of holding 2 electrons.
• p-orbitals: Shaped like a dumbbell, there are three p orbitals in a p subshell, each capable of containing 2 electrons, allowing a total capacity of 6 electrons for the subshell.
• d-orbitals and f-orbitals: More complex in shape, they increase in number and electron capacity, with d orbitals having five orbitals (10 electrons total) and f orbitals having seven (14 electrons total).

These orbital shapes and capacities are determined by the principal quantum numbers and the types of subshells (s, p, d, f) in an atom. Grasping orbital concepts helps aptly predict how electrons distribute around the nucleus and, thus, participate in chemical bonding.

Atomic Structure

At the foundation of chemistry lies atomic structure, which describes an atom's composition and the forces binding it. An atom consists of a dense nucleus of protons and neutrons, around which electrons are dynamically organized. This organization of electrons in various orbitals forms the crux of atomic behavior. Key points related to atomic structure include:

• The atomic number, equal to the number of protons, uniquely identifies an element and determines its position in the periodic table.
• The neutron number, varying within elements, accounts for isotopes which possess the same number of protons but differ in mass.
• This atomic schema influences atomic mass, electron configuration, and energy levels within the atom.

Comprehending atomic structure elucidates how atoms form molecules and compounds, impacting everything from the microscopic level, such as enzyme reactions in your body, to macroscopic level phenomena, like the materials used in technology. Recognizing the interplay between protons, neutrons, and electrons contributes to a thorough understanding of chemical reactions and material properties.