To determine the most reactive metal among the given elements, we need to understand the trend in the periodic table, specifically for alkali metals (Group 1 elements).
Alkali metals are known for their high reactivity, and their reactivity increases as we move down the group. This is because:
- The atomic size increases down the group.
- The outermost electron becomes further from the nucleus, reducing the electrostatic force of attraction between the nucleus and the valence electron.
- Thus, the outermost electron is more easily lost, increasing the reactivity of the element.
Let's examine the elements provided in the first table, focusing on the alkali metals:
- Li (Lithium) with atomic number 3
- Na (Sodium) with atomic number 11
- K (Potassium) with atomic number 19
- Rb (Rubidium) with atomic number 37
- Cs (Cesium) with atomic number 55
- Fr (Francium) with atomic number 87
As we move down this group:
- Lithium (Li) is the least reactive among these.
- Francium (Fr) is the most reactive because it is at the bottom of Group 1.
Therefore, among the four elements presented, Francium (Fr) with atomic number 87 is the most reactive metal.
The correct location of the most reactive metal in the provided image is:
\begin{tabular}{|c|c|}
\hline
... & ... \\
... & ... \\
\hline
...\ & ... \\
... & ... \\
\hline
...\ & ... \\
... & ... \\
\hline
... & ... \\
... & ... \\
\hline
... & ... \\
... & ... \\
\hline
87 (Fr) & 88 (Ra) \\
\hline
\end{tabular}
Thus, the correct answer is Fr (Francium) located in the bottom-left corner of the periodic table section provided.
