08. Why are electrons shared unequally?

Why are electrons shared unequally?

Due to bonded atoms having differences in electronegativity

What is electronegativity?

Ability of atom in molecule to attract an electron in a covalent bond

What shows the ability of an atom to pull electrons?

Linus pauling scale

What does the linus pauling scale show?

0-4 scale showing ability of atom to pull electrons

What is the highest linus pauling scale value? What does this mean?

4.0 -> this atom has greatest ability to pull electrons

How does electronegativity change across a period?

Increases

Why does electronegativity increase across a period?

More protons in nucleus, constant shielding of electrons, Attraction between nucleus and electrons increase

What happens to electronegativity down a group?

Decreases

Why does electronegativity decrease down the group?

Increased radius because increased energy levels, increased shielding, weaker nuclear charge and attraction between nucleus and electrons

What is a dipole?

When 2 bonding atoms will have an electronegativity difference unless they are the same

How is a dipole formed?

Shifts in electron density of a bond can cause covalent bonds to become slightly ionic

What is the most electronegative element?

Fluorine

What is the least electronegative element?

Francium

What electronegativity difference is covalent?

0-0.4

What difference in electronegativity values is polar covalent?

0.9

What difference in electronegativity difference is strong polar covalent?

1.4