Question

In the f-block elements differentiating electron enters into f-orbital of shell.

Short answer

Answer: The differentiating electron in f-block elements is the electron that distinguishes an element from the preceding element in the periodic table. It enters the f-orbital, which plays a significant role in configuring the electron configuration and determining the unique properties of f-block elements, also known as inner transition elements.

Step-by-step solution

1. Understanding f-block elements

F-block elements are a group of elements in the periodic table that are also known as inner transition elements. They are located in the two separate rows at the bottom of the periodic table, called the Lanthanide and Actinide series. These elements have electrons filling the f-orbitals in their electron configuration.

2. Differentiating electrons

A differentiating electron is the electron that distinguishes an element from the preceding element in the periodic table. In f-block elements, the differentiating electron enters the f-orbital, which is responsible for the unique properties of these elements.

3. Differentiating electron entering the f-orbital

For the f-block elements, the transition between orbitals occurs in the f-orbital, instead of the s, p, or d orbitals as found in other element groups. As a result, the differentiating electron enters the f-orbital, helping to configure the electron configuration and thus the properties of the f-block elements. For example, consider the Lanthanide series element, Cerium (Ce). Its electron configuration can be written as [Xe] 4f^1 5d^1 6s^2, where the differentiating electron enters the 4f orbital. This differentiating electron is responsible for the unique properties of Cerium as it distinguishes it from the preceding element Lanthanum (La) with an electron configuration of [Xe] 5d^1 6s^2.

Key concepts

Inner Transition Elements

Understanding the inner transition elements is crucial as they hold exceptional properties due to their unique electron configuration. The name 'inner transition elements' stems from their placement in the periodic table as well as their electronic structure. Rather than being situated in the main body of the periodic table, these elements are found in two rows at the bottom, separate from the rest.

Essentially, inner transition elements consist of two series: the Lanthanide and Actinide series. What characterizes these elements is the gradual filling of their f-orbitals with electrons as we move across the series. Unlike the more familiar s or p orbitals, f-orbitals have a more complex structure which affects the chemistry and physics of these elements. The fact that their f-orbitals are shielded by other electrons in the 'outer' orbitals gives these elements their 'inner' label.

Electron Configuration

Delve into the electron configuration of inner transition elements, it's essential to grasp how the differentiating electron defines each element's chemical and physical properties. In general, electron configuration refers to the distribution of electrons in an atom's orbitals. Each element has a unique electron configuration that explains much about its behavior and position in the periodic table.

When it comes to f-block elements, their distinctive electron configuration includes the f-orbitals, which are not filled in a simple, straightforward way like s or p orbitals. The f-orbitals can house up to 14 electrons, and these occupy a space that is 'inner', or deeper within the atom, compared to other orbitals. The specific electron configuration for any f-block element indicates where its differentiating electron is placed, which is central to the formation of its electronic structure and thus its unique properties.

Lanthanide and Actinide Series

The Lanthanide and Actinide series represent the two rows of the f-block and showcase distinctive properties because of their differing electron configurations. Each series corresponds to the filling of the 4f and 5f orbitals, respectively.

The Lanthanide series includes elements with atomic numbers from 57 to 71 and is known for members with high magnetic susceptibility and specific optical properties due to the electrons in the 4f orbitals. These elements are often dubbed as 'rare earth metals' and are widely used in electronics, magnets, and various high-tech applications.

Conversely, the Actinide series encompasses elements from atomic number 89 to 103. These are noted for their radioactive properties, with many of these elements being synthetic and highly unstable. Their electron configuration involves the filling of 5f orbitals, which considerably affects their chemical reactivity and also makes them suitable for use in nuclear energy and weaponry.

It's interesting to note that the properties of the elements in both series become less predictable as the 4f and 5f orbitals fill, due to their complex interactions and the shielding effect from the outer electrons.