Question

State whether the following statements are true or false. The inert gas present in the second long period is Xe.

Short answer

Answer: The inert gas present in the second long period of the periodic table is Argon (Ar).

Step-by-step solution

Understand the Periodic Table and Inert Gases

The periodic table is organized into rows called periods and columns called groups. Inert gases, also known as noble gases, are elements that have a full outer electron shell and are very stable. They are found in Group 18 or 8A of the periodic table.

Identify the Second Long Period

The first row in the periodic table is known as the “short” period, and it contains only two elements (H and He). The second row, the first “long” period, contains eight elements (Li through Ne). The third row is the second “long” period (Na through Ar). Thus, the second long period comprises elements from atomic numbers 11-18.

Determine Inert Gas in the Second Long Period

In the second long period (Na through Ar), the last element of the row (Ar) is the inert gas, as it belongs to Group 18. Ar is Argon with the atomic number 18.

Compare the Identified Inert Gas with Xe

We have identified Argon (Ar) as the inert gas in the second long period of the periodic table, whereas the statement mentioned Xenon (Xe). Therefore, the statement is incorrect.

Conclusion

The statement "The inert gas present in the second long period is Xe" is false. The inert gas present in the second long period of the periodic table is Argon (Ar), not Xenon (Xe).

Key concepts

Periodic Table Organization

When diving into chemistry, one of the most fundamental tools at a student’s disposal is the periodic table. This table is not just a random assortment of elements, but a well-organized system based on atomic numbers, electron configurations, and recurring chemical properties. The periodic table is arranged in rows called periods and columns called groups. The periods correspond to the number of electron shells an atom has, while the groups contain elements with similar properties, often sharing the same number of electrons in their outermost shell.

Understanding this organization is crucial for navigating the table. For example, every group has a unique characteristic that defines its elements. Group 18, which is the rightmost column of the table, houses the noble gases, also known as inert gases, which are particularly notable for their lack of reactivity. This is a result of their complete outer electron shells, which we'll explore in more depth in a following section. So, to rightly refute the problematic exercise statement, a comprehending of periodic table organization is essential.

Noble Gases

Known for their remarkable lack of chemical reactivity, noble gases are a unique group of elements. This family consists of Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), and Radon (Rn). The reason why they are referred to as 'inert' or 'noble' is due to the fact that their outer electron shells are completely filled, making them typically uninterested in forming bonds with other elements.

For instance, in the exercise at hand, an understanding of which element falls into which period and group helps to identify Argon (Ar) as the inert gas in the second long period of the periodic table, not Xenon (Xe) which actually resides in the fifth period. Identifying noble gases requires awareness of both their position on the periodic table and their electron configuration properties.

Electron Shell Configuration

Delving into the electron shell configuration sheds light on why certain elements behave the way they do. Atoms have electron shells that can be envisioned as orbits around the nucleus where electrons reside. The number of electrons that can fill these shells follow a specific order guided by the rules of quantum mechanics. The first shell can hold up to 2 electrons, the second up to 8, and so on, increasing as shells move away from the nucleus.

The electron shell configuration is paramount for predicting an element's chemical behavior, as atoms strive to reach the most stable, energetically favorable configuration. Noble gases naturally have a full outermost shell, which is why they don't typically engage in chemical reactions. These stable electron configurations can further help students understand why the statement in the exercise about the inert gas in the second long period being Xenon (Xe) is flawed—Xe has a full fourth electron shell, not the third that would be seen in second period elements.