Question 1

Which of the following best describes a polar covalent bond?

Accepted Answer

A bond where electrons are shared unequally due to a difference in electronegativity.

Question 2

What is the minimum electronegativity difference required for a bond to be considered polar covalent?

Accepted Answer

$$0.5$$

Question 3

Which of the following statements about nonpolar covalent bonds is correct?

Accepted Answer

They occur when atoms share electrons equally due to similar electronegativity.

Question 4

Electronegativity is best defined as:

Accepted Answer

The ability of an atom to attract electrons towards itself in a chemical bond.

Question 5

Which molecule below is most likely to be polar?

Accepted Answer

$$\mathrm{H_2O} ($$water)

Question 6

If a molecule has polar bonds but is symmetrical, what is the overall polarity of the molecule?

Accepted Answer

The molecule is always nonpolar.

Question 7

Which of the following best explains why $$\mathrm{H_2O} is a $$polar molecule?

Accepted Answer

It has a bent shape and an electronegativity difference between H and O.

Question 8

Given the electronegativity values: H = 2.1, O = 3.5, what is the electronegativity difference in a water molecule?

Accepted Answer

$$1.4$$

Question 9

Which of the following is required for a molecule to be polar?

Accepted Answer

It must have polar bonds and geometric asymmetry.

Question 10

A molecule of $$\mathrm{CO_2$} is $$nonpolar even though it contains polar bonds. Why?

Accepted Answer

The molecule is linear and the bond dipoles cancel each other out.

Question 11

Which of the following best describes the relationship between bond polarity and molecular polarity?

Accepted Answer

Molecular polarity depends on both bond polarity and molecular geometry.

Question 12

Which of the following is a real-world consequence of molecular polarity?

Accepted Answer

Polar molecules tend to have higher boiling points due to dipole-dipole interactions.

Question 13

Which of the following pairs of atoms would form a nonpolar covalent bond?

Accepted Answer

Cl and Cl

Question 14

If a molecule has an electronegativity difference of $$0.9$$, what type of bond is most likely present?

Accepted Answer

Polar covalent

Question 15

Which of the following is NOT a requirement for a molecule to be polar?

Accepted Answer

It must have an overall charge.

Covalent Bonds, Electronegativity, and Molecular Polarity

Study Guide - Practice Questions