Question

Arrange the elements \(\mathrm{Mg}, \mathrm{S},\) and \(\mathrm{Cl}\) in order of (a) increasing atomic radius. (b) increasing first ionization energy. (c) decreasing electronegativity.

Short answer

Question: Arrange the given elements (Mg, S, and Cl) in terms of their (a) increasing atomic radius, (b) increasing first ionization energy, and (c) decreasing electronegativity. Answer: (a) Mg > S > Cl, (b) Mg < S < Cl, (c) Cl > S > Mg.

Step-by-step solution

(a) Increasing Atomic Radius

To arrange the elements in order of increasing atomic radius, we can use the periodic trends for atomic radii. In the periodic table, atomic radius tends to increase from top to bottom in a group and decrease from left to right across a period. Looking at the periodic table, we can see that Mg is in Group 2, Period 3, S is in Group 16, Period 3, and Cl is in Group 17, Period 3. Since all of the elements are in the same period, we can focus on the general trend that atomic radius decreases from left to right across a period. Hence, the order of increasing atomic radii is: Mg > S > Cl.

(b) Increasing First Ionization Energy

To arrange the elements in order of increasing first ionization energy, we can again take advantage of the periodic trends for ionization energy. In the periodic table, first ionization energy tends to increase from left to right across a period and decrease from top to bottom in a group. Since all of the elements are in the same period, we can focus on the general trend that ionization energy increases from left to right across a period. Therefore, the order of increasing first ionization energy is: Mg < S < Cl.

(c) Decreasing Electronegativity

Finally, to arrange the elements in order of decreasing electronegativity, we will use the periodic trends for electronegativity. In the periodic table, electronegativity generally increases from left to right across a period and decreases from top to bottom in a group. As all of the elements are in the same period, we will focus on the general trend that electronegativity increases from left to right across a period. Therefore, the order of decreasing electronegativity is: Cl > S > Mg.