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intermolecular forces (between)

the electrostatic interactions between molecules.

forces that exist between molecules.

(in strongest to weakest order)

HYDROGEN BONDING 🌊

H-FON

  • When hydrogen bonds with fluorine, oxygen, or nitrogen.

  • These are very strong dipole-dipole interactions as FON are the most electronegative elements, creating the most strongly polarized bonds.

  • The greater the difference in charge, the stronger the interaction (never stronger than formal charges ahem ions though.)

  • More hydrogen bonds can not occur unless the compound was already in a hydrogen bond originally or in no bond.

DIPOLE-DIPOLE INTERACTIONS 😡❤️😊

What is a dipole?

A bond or molecule whose ends have opposite charges.

Attractive forces between the positive end of one polar molecule and the negative end of another polar molecule.

Non-polar molecules/bonds cannot form dipole-dipole interactions as they have no charge.

Example of a dipole-dipole interaction

Water molecules are polar bc oxygen is more electronegative than hydrogen, thus, will pull the electrons in the bond towards itself.

  • oxygen will have a negative charge as it has electron excess (needs to get rid of some)

  • hyrogens will have a positive charge as it has electron deficiency (lacking some)

When the vectors (charges) are combined and one side has a stronger pull (electronegativity) than the other side, forming a dipole.

Ion-Dipole

When ions make interactions with atoms with the opposite charge.

ion-dipole bond between water molecule and NaCl

Dipole-dipole

molecules will move in such a way as to always be making electrostatic interactions between the negative end of one dipole and the positive end of another dipole.

water molecules

DISPERSION FORCES 🁷🁷🁷🁷🁷🀷👈

DOMINOOOOOOS

  • it is what monoatomic species & non-polar covalent compounds can do.

  • a weak attraction occurs when a polar molecule induces a dipole in an atom or in a nonpolar molecule by disturbing the arrangement of electrons in the nonpolar species.

Momentary Dipole

  • When the electron cloud of an atom is SLIGHTLY lopsided, resulting in a small partial negative and positive charge.

  • Weaker than a formal dipole-dipole bond.

Induced Dipole

  • When momentary Dipole approaches another atom, the partial negativity gets repeled, moving to the other side of the atom and resulting in a slight dipole.

Thus, there will be a momentary dipole + induced dipole interaction.

momentary dipole + induced dipole interaction

intermolecular forces (between)

the electrostatic interactions between molecules.

forces that exist between molecules.

(in strongest to weakest order)

HYDROGEN BONDING 🌊

H-FON

  • When hydrogen bonds with fluorine, oxygen, or nitrogen.

  • These are very strong dipole-dipole interactions as FON are the most electronegative elements, creating the most strongly polarized bonds.

  • The greater the difference in charge, the stronger the interaction (never stronger than formal charges ahem ions though.)

  • More hydrogen bonds can not occur unless the compound was already in a hydrogen bond originally or in no bond.

DIPOLE-DIPOLE INTERACTIONS 😡❤️😊

What is a dipole?

A bond or molecule whose ends have opposite charges.

Attractive forces between the positive end of one polar molecule and the negative end of another polar molecule.

Non-polar molecules/bonds cannot form dipole-dipole interactions as they have no charge.

Example of a dipole-dipole interaction

Water molecules are polar bc oxygen is more electronegative than hydrogen, thus, will pull the electrons in the bond towards itself.

  • oxygen will have a negative charge as it has electron excess (needs to get rid of some)

  • hyrogens will have a positive charge as it has electron deficiency (lacking some)

When the vectors (charges) are combined and one side has a stronger pull (electronegativity) than the other side, forming a dipole.

Ion-Dipole

When ions make interactions with atoms with the opposite charge.

ion-dipole bond between water molecule and NaCl

Dipole-dipole

molecules will move in such a way as to always be making electrostatic interactions between the negative end of one dipole and the positive end of another dipole.

water molecules

DISPERSION FORCES 🁷🁷🁷🁷🁷🀷👈

DOMINOOOOOOS

  • it is what monoatomic species & non-polar covalent compounds can do.

  • a weak attraction occurs when a polar molecule induces a dipole in an atom or in a nonpolar molecule by disturbing the arrangement of electrons in the nonpolar species.

Momentary Dipole

  • When the electron cloud of an atom is SLIGHTLY lopsided, resulting in a small partial negative and positive charge.

  • Weaker than a formal dipole-dipole bond.

Induced Dipole

  • When momentary Dipole approaches another atom, the partial negativity gets repeled, moving to the other side of the atom and resulting in a slight dipole.

Thus, there will be a momentary dipole + induced dipole interaction.

momentary dipole + induced dipole interaction

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