Question

which of the following is the most electronegative?
a
b
mg
k

Explanation:

Step1: Recall electronegativity trend

Electronegativity increases across a period and decreases down a group in the periodic table.

Step2: Identify element positions

Ar (argon) is a noble - gas with a stable electron configuration and low electronegativity. Cl (chlorine) is a non - metal in group 17. Mg (magnesium) is a metal in group 2. K (potassium) is a metal in group 1.

Step3: Determine most electronegative

Non - metals are more electronegative than metals, and among the non - metals here, Cl has a high electronegativity due to its position in group 17.

Answer:

Cl