The question asks for the correct order of metallic character among the given elements: Beryllium (Be), Silicon (Si), Magnesium (Mg), and Potassium (K). The metallic character of elements refers to how easily an element can lose electrons to form positive ions. It generally increases down a group and decreases across a period from left to right in the periodic table.
Let's analyze each element's position in the periodic table:
Potassium (K) is located in Group 1 (Alkali Metals) and Period 4. Alkali metals are known for having a high metallic character because they can easily lose their one valence electron.
Magnesium (Mg) is found in Group 2 (Alkaline Earth Metals) and Period 3. It has a high metallic character, but not as high as Potassium because it is further to the right in the period.
Beryllium (Be) is also in Group 2 but in Period 2. It has a lower metallic character compared to Magnesium, as it is higher up in the group.
Silicon (Si) is located in Group 14 and Period 3. Silicon is a metalloid, which means it has properties between metals and non-metals, thus having the lowest metallic character among the given elements.
Based on this analysis, the correct order of metallic character descending (from least to most metallic) is: \(Si < Be < Mg < K\).
Thus, the correct answer is: \(Si < Be < Mg < K\).
