Answer :
We can determine the correct matching for the groups in the periodic table by recognizing the characteristic properties of each set of elements. Here is a step-by-step explanation:
1. The first group in the periodic table is the Alkali metals (Group 1). These elements are well known for their metallic nature, being very reactive and exhibiting the typical properties of metals. So, the characteristic property of this group is that they are a [tex]$ \textbf{metal} $[/tex].
2. The second group is the Alkaline earth metals (Group 2). Like the alkali metals, these elements are also metals with similar physical properties (although they are slightly less reactive). Thus, the property for this group is also [tex]$ \textbf{metal} $[/tex].
3. The Transition metals (located in the central block, Groups 3–12) are recognized by their variable oxidation states and metallic properties. Their most defining quality in this context is that they are all [tex]$ \textbf{metal} $[/tex].
4. The Metalloids are a set of elements (often found along the staircase line on the periodic table) that exhibit properties between those of metals and nonmetals. Their characteristic nature is best described as [tex]$ \textbf{metalloid} $[/tex].
5. Many of the elements in the p‐block (including nonmetals such as carbon, nitrogen, oxygen, and the noble gases) fall into the category of Nonmetals. Their defining property is that they are [tex]$ \textbf{nonmetal} $[/tex].
6. The Halogens (typically found in Group 17) are also considered nonmetals because of their properties, even though they have unique trends regarding reactivity. Their property is [tex]$ \textbf{nonmetal} $[/tex].
7. The Noble gases (Group 18) are inert gases and clearly display nonmetallic behavior. Thus, their property is [tex]$ \textbf{nonmetal} $[/tex].
8. Finally, the Lanthanides and Actinides are usually set apart at the bottom of the periodic table. Because many of their properties are less familiar or may vary, their characteristic property is often labeled as [tex]$ \textbf{unknown} $[/tex].
Compiling these results, we have the following matching:
[tex]$$
\begin{aligned}
\text{Alkali metals (Group 1)} &\to \text{metal}, \\
\text{Alkaline earth metals (Group 2)} &\to \text{metal}, \\
\text{Transition metals (Groups 3–12)} &\to \text{metal}, \\
\text{Metalloids} &\to \text{metalloid}, \\
\text{Nonmetals} &\to \text{nonmetal}, \\
\text{Halogens} &\to \text{nonmetal}, \\
\text{Noble gases} &\to \text{nonmetal}, \\
\text{Lanthanides \& Actinides} &\to \text{unknown}.
\end{aligned}
$$[/tex]
Thus, the final matching is:
- Alkali metals (Group 1): [tex]$ \textbf{metal} $[/tex]
- Alkaline earth metals (Group 2): [tex]$ \textbf{metal} $[/tex]
- Transition metals (Groups 3–12): [tex]$ \textbf{metal} $[/tex]
- Metalloids: [tex]$ \textbf{metalloid} $[/tex]
- Nonmetals: [tex]$ \textbf{nonmetal} $[/tex]
- Halogens: [tex]$ \textbf{nonmetal} $[/tex]
- Noble gases: [tex]$ \textbf{nonmetal} $[/tex]
- Lanthanides \& Actinides: [tex]$ \textbf{unknown} $[/tex]
This is the detailed reasoning behind the assignment of each group to its characteristic property.
1. The first group in the periodic table is the Alkali metals (Group 1). These elements are well known for their metallic nature, being very reactive and exhibiting the typical properties of metals. So, the characteristic property of this group is that they are a [tex]$ \textbf{metal} $[/tex].
2. The second group is the Alkaline earth metals (Group 2). Like the alkali metals, these elements are also metals with similar physical properties (although they are slightly less reactive). Thus, the property for this group is also [tex]$ \textbf{metal} $[/tex].
3. The Transition metals (located in the central block, Groups 3–12) are recognized by their variable oxidation states and metallic properties. Their most defining quality in this context is that they are all [tex]$ \textbf{metal} $[/tex].
4. The Metalloids are a set of elements (often found along the staircase line on the periodic table) that exhibit properties between those of metals and nonmetals. Their characteristic nature is best described as [tex]$ \textbf{metalloid} $[/tex].
5. Many of the elements in the p‐block (including nonmetals such as carbon, nitrogen, oxygen, and the noble gases) fall into the category of Nonmetals. Their defining property is that they are [tex]$ \textbf{nonmetal} $[/tex].
6. The Halogens (typically found in Group 17) are also considered nonmetals because of their properties, even though they have unique trends regarding reactivity. Their property is [tex]$ \textbf{nonmetal} $[/tex].
7. The Noble gases (Group 18) are inert gases and clearly display nonmetallic behavior. Thus, their property is [tex]$ \textbf{nonmetal} $[/tex].
8. Finally, the Lanthanides and Actinides are usually set apart at the bottom of the periodic table. Because many of their properties are less familiar or may vary, their characteristic property is often labeled as [tex]$ \textbf{unknown} $[/tex].
Compiling these results, we have the following matching:
[tex]$$
\begin{aligned}
\text{Alkali metals (Group 1)} &\to \text{metal}, \\
\text{Alkaline earth metals (Group 2)} &\to \text{metal}, \\
\text{Transition metals (Groups 3–12)} &\to \text{metal}, \\
\text{Metalloids} &\to \text{metalloid}, \\
\text{Nonmetals} &\to \text{nonmetal}, \\
\text{Halogens} &\to \text{nonmetal}, \\
\text{Noble gases} &\to \text{nonmetal}, \\
\text{Lanthanides \& Actinides} &\to \text{unknown}.
\end{aligned}
$$[/tex]
Thus, the final matching is:
- Alkali metals (Group 1): [tex]$ \textbf{metal} $[/tex]
- Alkaline earth metals (Group 2): [tex]$ \textbf{metal} $[/tex]
- Transition metals (Groups 3–12): [tex]$ \textbf{metal} $[/tex]
- Metalloids: [tex]$ \textbf{metalloid} $[/tex]
- Nonmetals: [tex]$ \textbf{nonmetal} $[/tex]
- Halogens: [tex]$ \textbf{nonmetal} $[/tex]
- Noble gases: [tex]$ \textbf{nonmetal} $[/tex]
- Lanthanides \& Actinides: [tex]$ \textbf{unknown} $[/tex]
This is the detailed reasoning behind the assignment of each group to its characteristic property.
