Uploaded August 2025 | Updated September 2026, 2 weeks ago
Electronegativity and Bonding
Dr. DeBacco
Electronegativity
Electronegativity is a chemical property that describes how strongly an atom attracts shared electrons when forming a bond with another atom.
Features
Symbol: χ (Greek letter chi)
Range: Typically from 0.7 (low) to 4.0 (high)
This is just a scale so no unit
What Influences Electronegativity?
Atomic number:
More protons = stronger pull-on electrons.
Distance of valence electrons from nucleus:
Closer electrons feel a stronger attraction.
Electron shielding:
Inner electrons can block the pull of the nucleus
Electronegativity and Oxidation Number
Oxidation number- a number assigned to an atom in a chemical compound to indicate its degree of oxidation or reduction.
This can help to track electron distribution in molecules
Higher the Oxidation Number the Higher the Electronegativity
Electronegativity and Bonding
Electronegativity directly influences the type of bond formed between atoms.
Large Difference
Leads to ionic bonding
Smaller Differences
Result in covalent bonds
Depending on difference it can be polar or nonpolar
Helps to Predict
Bond type (ionic, polar covalent, non-polar covalent)
Molecular polarity
Reactivity and chemical behavior
For example, in water (H₂O), oxygen is more electronegative than hydrogen, so it pulls the shared electrons closer, creating a polar molecule with partial charges.
Electronegativity and the Periodic Table
Across a Period (Left to Right)- Increases
Down a Group (Top to Bottom)- Decreases
Fluorine (F) is the most electronegative element (≈3.98 on the Pauling scale).
Francium (Fr) is among the least electronegative (≈0.7).
Link to Lecture Slides: drive.google.com/file/d/1pMxCRHPxrGuErdZJDr22VbKAgNUq8ZOx/view?usp=drive_link
*Due to the description character limit the full work cited for "Electronegativity and Bonding" can be viewed at... docs.google.com/document/d/1yqVe9p6WqtLhs4_CuVoPM-1P9Co6ntUS/edit?usp=drive_link&ouid=104237452697237972847&rtpof=true&sd=true
Electronegativity and Bonding
Dr. DeBacco
Electronegativity
Electronegativity is a chemical property that describes how strongly an atom attracts shared electrons when forming a bond with another atom.
Features
Symbol: χ (Greek letter chi)
Range: Typically from 0.7 (low) to 4.0 (high)
This is just a scale so no unit
What Influences Electronegativity?
Atomic number:
More protons = stronger pull-on electrons.
Distance of valence electrons from nucleus:
Closer electrons feel a stronger attraction.
Electron shielding:
Inner electrons can block the pull of the nucleus
Electronegativity and Oxidation Number
Oxidation number- a number assigned to an atom in a chemical compound to indicate its degree of oxidation or reduction.
This can help to track electron distribution in molecules
Higher the Oxidation Number the Higher the Electronegativity
Electronegativity and Bonding
Electronegativity directly influences the type of bond formed between atoms.
Large Difference
Leads to ionic bonding
Smaller Differences
Result in covalent bonds
Depending on difference it can be polar or nonpolar
Helps to Predict
Bond type (ionic, polar covalent, non-polar covalent)
Molecular polarity
Reactivity and chemical behavior
For example, in water (H₂O), oxygen is more electronegative than hydrogen, so it pulls the shared electrons closer, creating a polar molecule with partial charges.
Electronegativity and the Periodic Table
Across a Period (Left to Right)- Increases
Down a Group (Top to Bottom)- Decreases
Fluorine (F) is the most electronegative element (≈3.98 on the Pauling scale).
Francium (Fr) is among the least electronegative (≈0.7).
Link to Lecture Slides: drive.google.com/file/d/1pMxCRHPxrGuErdZJDr22VbKAgNUq8ZOx/view?usp=drive_link
*Due to the description character limit the full work cited for "Electronegativity and Bonding" can be viewed at... docs.google.com/document/d/1yqVe9p6WqtLhs4_CuVoPM-1P9Co6ntUS/edit?usp=drive_link&ouid=104237452697237972847&rtpof=true&sd=true
