Question

Choose the most electronegative element of period III from the following elements- Chlorine, Helium, Phosphorus, Magnesium, and Cesium.

Answer 1

1. Electronegativity is the tendency of an atom to attract the shared pair of electrons towards itself.
2. Trend of the electronegativity: The electronegativity of the atom decreases on moving down the group and increases on moving from left to right in a periodic table.
3. Helium (He) belongs to period 1 and it is a noble gas that has zero electronegativity.
4. Magnesium (Mg has electronegativity 1.2), Phosphorus (P has electronegativity 2.1), and Chlorine (Cl has electronegativity 3.0) belong to period 3.
5. Cesium (Cs has electronegativity 0.7) belongs to period 5.
6. As the electronegativity increases from left to right, thus Chlorine is the most electronegative atom of period III.