Practice Electronegativity in Chemistry

Use these practice problems to test your method after reviewing the concept explanation and worked examples.

Quick Recap

A dimensionless measure of how strongly an atom attracts the shared electrons in a covalent bond toward itself, quantified on the Pauling scale from about 0.7 (cesium/francium) to 3.98 (fluorine).

How 'greedy' an atom is for electrons. Fluorine is most greedy.

Showing a random 20 of 50 problems.

Example 1

medium
In NH3\text{NH}_3, identify the bond polarity for each N–H bond and the direction of dipole.

Example 2

easy
Between Na and Cl, which atom is more electronegative?

Example 3

easy
Which is more electronegative: oxygen or sulfur?

Example 4

medium
A bond has ΔEN=0.4\Delta EN = 0.4. Classify it as nonpolar covalent, polar covalent, or ionic (cutoffs ~0.5 and ~1.7).

Example 5

easy
Down a group of the periodic table, how does electronegativity change?

Example 6

medium
Order the bonds CClC-Cl, CFC-F, CBrC-Br by increasing polarity (halogen EN: Cl 3.0, F 4.0, Br 2.8).

Example 7

challenge
Explain why electronegativity does NOT increase smoothly down group 1 even though nuclear charge increases.

Example 8

easy
In a bond between H (2.1) and Cl (3.0), which atom carries the partial negative charge?

Example 9

easy
Do noble gases like neon have high tabulated electronegativity values?

Example 10

medium
Which has greater EN: O (period 2) or S (period 3), and why?

Example 11

medium
Which atom in a COC-O bond is partial negative, given C = 2.5 and O = 3.5?

Example 12

medium
In the molecule HF, the electronegativity of H is 2.1 and F is 4.0. Describe the bond polarity and indicate the direction of the dipole.

Example 13

medium
Which bond is more polar, C–H or O–H? Use these electronegativity values: C = 2.5, H = 2.1, O = 3.5.

Example 14

medium
Rank C, N, O by increasing electronegativity.

Example 15

easy
Down a group, how does electronegativity generally change?

Example 16

easy
In an H–O bond (H = 2.1, O = 3.5), which atom carries the partial negative charge?

Example 17

medium
Classify the bond in KBr\text{KBr} using EN values K = 0.8, Br = 2.8.

Example 18

medium
In COCO, the bond's δ\delta^- end is on which atom (O = 3.5, C = 2.5)?

Example 19

hard
Predict whether HBr\text{HBr} or HI\text{HI} has a larger dipole moment, using EN values H 2.1, Br 2.8, I 2.5.

Example 20

medium
The electronegativity difference in HFH-F is 3.982.203.98 - 2.20. What is ΔEN\Delta EN?