Question

For the elements in the third period of the Periodic Table, which property decreases
consistently from sodium to chlorine?
a. Electrical Conductivity
b. Ionization Energy
c. Melting Point
d. Radius of the atom​

Answer 1

Answer:

On moving from left to right in a period, the chemical reactivity of elements first decreases and then increases. On moving from left to right in a period, the number of valence electrons increases from 1 to 8. On moving from left to right in a period, the atomic size decreases; the size of the atoms decreases. Since the atomic size decrease when we move from left to right in a period, therefore, electronegativity increases in moving left to right. Atomic size increases when moving down in a group thus electronegativity decreases when we move from top to bottom in the periodic table.  

Metallic character decreases as you move across a period in the periodic table from left to right. This occurs as atoms more readily accept electrons to fill a valence shell than lose them to remove the unfilled shell.