Question

In which period and which group is the element that has the ground-state electron configuration \(1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{2} 3 d^{3}\) ? Which element is this?

Short answer

The element with the ground-state electron configuration \(1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^3\) is Vanadium (V), which has an atomic number of 23. It is located in Period 4 and Group 5 on the periodic table.

Step-by-step solution

Determine the Total Number of Electrons

To find the total number of electrons in the element, we will add up the number of electrons in each energy level. In the given electron configuration: \(1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^3\) We see that there are: - 2 electrons in 1s - 2 electrons in 2s - 6 electrons in 2p - 2 electrons in 3s - 6 electrons in 3p - 2 electrons in 4s - 3 electrons in 3d Adding these up, the total number of electrons is 23.

Identify the Highest Energy Level and Valence Electrons

The element's highest energy level is the highest principal quantum number \(n\), which is 4 in this case. Thus, the element is in the fourth period. Now, we need to determine the number of valence electrons. Valence electrons are the electrons in the outermost energy level (4s and 3d). Here, there are 2 electrons in 4s and 3 electrons in 3d, yielding a total of 5 valence electrons.

Determine the Element's Position on the Periodic Table

Using the total number of electrons (23), we can determine the element's atomic number, which is also 23. On the periodic table, elements are arranged by their atomic number. Now, to find the group, we need to identify the number of valence electrons. Since it has 5 valence electrons (2 in 4s and 3 in 3d), the element is in group 5.

Identify the Element's Period, Group, and Name

Based on the element's atomic number, it is placed in: - Period 4 - Group 5 The element with atomic number 23 is Vanadium (V). In conclusion, the element with the ground-state electron configuration \(1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^3\) is Vanadium (V), and it is located in Period 4 and Group 5 on the periodic table.

Key concepts

Understanding the Periodic Table

The periodic table is a systematic arrangement of the chemical elements, ordered by their atomic numbers, electron configurations, and recurring chemical properties. Elements are listed in rows called periods and columns called groups.

As students look at the periodic table, they will notice that each period corresponds to the highest energy level that electron occupies in the ground state. So if an element has its highest energy electrons in the fourth shell, it will be found in the fourth period. Each group contains elements with the same number of valence electrons, which makes them exhibit similar chemical behavior. For example, most elements in group 1 have one valence electron and are very reactive metals.

Using the periodic table, students can determine the properties of an element, predict the types of chemical reactions it will partake in, and understand its atomic structure just at a glance. It's an indispensable tool for chemistry students and professionals alike.

Valence Electrons and Chemical Properties

Valence electrons are the electrons on an atom's outermost Energetic shell that are involved in forming bonds with other atoms. These electrons play a crucial role in determining an element's chemical properties and its behavior in reactions.

For instance, in exercise solutions, when students are asked to determine the valence electrons for an element, they are identifying the electrons that are available for bonding. In the case of the element with electron configuration 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^3, there are 5 valence electrons (2 in 4s and 3 in 3d). This information is not just academic; it provides insight into how this element would react with other elements – for example, how it might form compounds or what type of ions it could form.

Owning to this, students who understand how to count valence electrons can more easily grasp concepts related to chemical bonding and molecular structure.

The Significance of Atomic Number

An element's atomic number is one of its most fundamental properties, as it tells us the number of protons in the nucleus of an atom of that element. Because each element has a unique number of protons, the atomic number also uniquely identifies each element on the periodic table.

When a student is solving problems related to electron configurations, such as 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^3, determining the sum of the electrons gives us the atomic number (23 in this case). This allows students to quickly look up the element on the periodic table, as in our example, which led us to Vanadium (V).

Understanding atomic numbers and how they relate to an element's position on the periodic table helps students make connections between electron configuration, element identity, and even reactivity and other chemical properties. This is vital when they move from exercises to real-world chemical applications.