Unit 7: Covalent Bonding

What happens to the electrons in a covalent bond?

The electrons are SHARED.

If two atoms have the same electronegativity, what kind of bond is formed?

Nonpolar covalent (electrons are shared equally).

What is the difference between a polar covalent bond and a nonpolar covalent bond?

In polar bonds, electrons are shared unequally, and in nonpolar covalent bonds, electrons are shared equally.

If a bond is polar between two atoms, what is the difference in the electronegativity between the two atoms?

It is greater than 0.4 but less than 2.0.

If two fluorine atoms are bonded, what do you know about the electronegativity values of the two atoms?

The electronegativity values are identical.

What kind of bond is formed between those two fluorines?

A nonpolar covalent bond, because the difference in the electronegativity between the two fluorines is the identical O atoms, since it’s smaller than 0.4, the bond between the two identical F MUST be nonpolar.

Every nonmetal atom in a Lewis structure should be surrounded by how many electrons when bonded (with the exception of H and He)?

Eight electrons for stability, following the octet rule (2 for H and He).

How many extra electrons are in the nitrate ion, NO₃⁻¹?

The nitrate ion has one extra electron due to its negative charge.

How many electrons TOTAL should be drawn in the Lewis structure for NH₄⁺¹?

The Lewis structure for NH₄⁺¹ should include a total of 8 electrons, accounting for the 5 valence electrons from nitrogen and 4 from the four hydrogen atoms, minus one for the positive charge.

What does VSEPR stand for?

Valence Shell Electron Pair Repulsion

What is the purpose of VSEPR theory?

3D shape of the molecule.

Describe how VSEPR theory determines the shape of a molecule.

Electrons are repelled by each other and want to be far away from each other.