Hydrogen has an electronegativity value of about 2.20 on the Pauling scale, which is relatively high when compared to other elements in its group and period. One reason for this high value lies in hydrogen’s unique position in the periodic table. While it is located in Group 1, which contains alkali metals that typically have low electronegativities, hydrogen is distinct in its behavior and properties.
Hydrogen is a non-metal and can form covalent bonds, sharing electrons with other non-metals. Its small atomic size allows it to attract electrons more effectively than larger atoms, which contributes to its greater electronegativity. Moreover, hydrogen often forms bonds with highly electronegative elements like oxygen and nitrogen, showcasing its ability to form polar covalent bonds.
In summary, while hydrogen is in Group 1, its non-metallic character, small atomic radius, and ability to attract electrons more strongly contribute to its relatively high electronegativity value.