A chemical bond formed when two atoms share one or more pairs of valence electrons, creating a strong attractive force that holds them together as a molecule.
Atoms hold electrons together like kids sharing a toy. Neither gives it away.
Showing a random 20 of 50 problems.
Example 1
medium
Why can a covalent bond like the triple bond in N2 be stronger than many ionic bonds?
Example 2
hard
A 0.50 mol sample of N2 is completely dissociated into atoms. Using bond energy 945 kJ/mol, find the energy required.
Example 3
challenge
Methane CH4 and water H2O are both covalent. Explain why carbon forms 4 bonds but oxygen forms only 2.
Example 4
medium
Nitrogen gas is N2 with a triple bond. How many electrons are shared, and why is N2 so stable?
Example 5
medium
Compare the bond strengths of single, double, and triple C-C bonds (in general terms).
Example 6
easy
How many electrons does hydrogen need to share to complete its outer shell?
Example 7
easy
Which pair forms a covalent bond: two oxygen atoms, or sodium and fluorine?
Example 8
easy
A covalent bond forms when atoms ____ electrons.
Example 9
challenge
A substance has a low melting point, does not conduct electricity even when molten, and exists as discrete units. Identify the bond type and justify each clue.
Example 10
medium
Distinguish a polar covalent bond from a nonpolar covalent bond using H-Cl versus Cl-Cl.
Example 11
medium
Draw the dot structure (count electrons) for H2O and state the number of lone pairs on oxygen.H₂O: how many lone pairs are on oxygen?
Example 12
medium
Why do covalent molecular substances like sugar not conduct electricity, even when melted?
Example 13
easy
In water, how does each O-H covalent bond help oxygen and hydrogen?
Example 14
hard
Compare bond lengths: C-C, C=C, and C≡C. Order from longest to shortest.
Example 15
easy
In O2, how many electrons total are shared between the two oxygen atoms?
Example 16
hard
In SO2, the central sulfur has one double bond and one single bond (with resonance). How many total bond pairs and lone pairs are around S?
Example 17
easy
How many electrons are in one single covalent bond?
Example 18
challenge
In O3 (ozone), the central O has formal bonds drawn as one single and one double bond. What is the average bond order between the central O and each terminal O?
Example 19
medium
In CH4, how many shared electron pairs surround the central carbon?CH₄: how many shared electron pairs surround the central carbon?
Example 20
medium
Predict whether C2H4 (ethylene) contains a single, double, or triple C-C bond.C₂H₄: is the C-C bond single, double, or triple?