Question 1

Which of the following statements best describes electronegativity?

Accepted Answer

Electronegativity measures how strongly an atom attracts electrons in a chemical bond.

Question 2

Which atom has the highest electronegativity according to the periodic trend?

Accepted Answer

Fluorine (F)

Question 3

Given the electronegativity difference ($$\Delta EN) $$between Na and Cl is 2.1, what type of bond is formed in NaCl?

Accepted Answer

Ionic bond

Question 4

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

Accepted Answer

Br and Br

Question 5

What is the correct Lewis structure for the nitrate ion ($$NO_3$$^-$$)?

Accepted Answer

A structure with one double bond and two single bonds, with resonance between the oxygen atoms.

Question 6

Which formula is used to calculate the formal charge of an atom in a Lewis structure?

Accepted Answer

$$FC = V - N - \frac{B}{2}$$

Question 7

Which molecule below exhibits resonance?

Accepted Answer

SO$$_2$$

Question 8

What is the percent ionic character of the CO bond if the electronegativity difference ($$\Delta EN) is 0.89$$?

Accepted Answer

Approximately 20%

Question 9

Which of the following molecules has an expanded octet in its Lewis structure?

Accepted Answer

PF$$_5$$

Question 10

In the Lewis structure of $$ClO_3$$^-$$, what is the formal charge on the central chlorine atom?

Accepted Answer

0

Question 11

Which of the following best explains why the bonds in $$SO_2$$ are equivalent in nature?

Accepted Answer

Because $$SO_2$$ exhibits resonance, making the bonds intermediate between single and double.

Question 12

Which molecule below is polar due to its molecular geometry?

Accepted Answer

SF$$_2$$

Question 13

What is the correct Lewis structure for $$CH_2O ($$formaldehyde)?

Accepted Answer

Central C atom double bonded to O and single bonded to two H atoms.

Question 14

Which of the following ions requires resonance structures to accurately represent its Lewis structure?

Accepted Answer

NO$$_3^-$$

Question 15

Which molecule or ion below does NOT obey the octet rule?

Accepted Answer

BCl$$_3$$

Question 16

What is the molecular geometry of $$IF_5$$?

Accepted Answer

Square pyramidal

Question 17

Which of the following molecules has a dipole moment?

Accepted Answer

H$$_2O$$

Question 18

Which of the following is the correct order of increasing bond polarity for the following pairs: H—Cl, H—F, H—I?

Accepted Answer

H—I \u003c H—Cl \u003c H—F

Question 19

Which of the following best describes the effect of an electric field on HF molecules?

Accepted Answer

HF molecules align with the field due to their dipole moment.

Electronegativity, Bond Polarity, and Lewis Structures: Study Guide

Study Guide - Practice Questions