Determining Interparticle Force

[cheechnchong]

Homework Statement

Indentify the interparticle force between the solvent and solute. If you feel that one force holds more solute to solvent, then list them in order of strongest to weakest.

(a) CF3CH2OH in H2O
(b) NH4+ in H20(l)
(c) C5H12 in C9H20
(d) NO3- (nitrate ion) in CH3OH
(e) CH3COO- (acetate ion) in H2O

The Attempt at a Solution

(a) Hydrogen Force
(b) Ion- Dipole Force
(c) Dispersion Force
(d) Hydrogen Force
(e) Ion-Dipole Force

I always confuse myself when I'm doing these types of questions...What is the general rule I should follow to have success in answering these questions? firstly, am i right with my attempt?

THANKS!

 

[Oaksinstructor]

Dispersion forces are the attractions between opposite ends of temporary induced dipoles, Dipole-Dipole forces are the attraction between oppositely charged ends of permanent dipoles, and Hydrogen bonds are the unusually strong diploe-diploe forces in hydrogen compounds of Flourine, Oxygen, and Nitrogen.
Permanent diploes are the result of the separation of charge in bonds between atoms of different electronegativity (ex. H-Cl). A temporary diploe is the result of shifts in electron density (ex. the dispersion forces between H2 molecules)
and Finally: Dispersion forces are weak (but can be strong in larger atoms), dipole-diploe forces are moderate, and hydrogen bonding is the strongest.

 

[Blueshift5]

it is important to understand the fundamental forces that govern the interactions between particles in a solution. In order to determine the interparticle force between a solvent and solute, we must consider the types of particles involved and the nature of their interactions.

In the first example, CF3CH2OH (a polar molecule) in H2O (a polar solvent), the dominant interparticle force would be hydrogen bonding. This is because both the solvent and solute contain polar covalent bonds and partial charges, allowing for strong interactions between the positively charged hydrogen atoms and the negatively charged oxygen atoms.

In the second example, NH4+ (an ion) in H2O (a polar solvent), the dominant interparticle force would also be ion-dipole interactions. This is because the solvent molecules have partial charges that can interact with the charged NH4+ ion.

In the third example, C5H12 (a nonpolar molecule) in C9H20 (a nonpolar solvent), the dominant interparticle force would be dispersion forces. These are weak forces that arise from temporary fluctuations in electron density in nonpolar molecules, allowing for short-lived dipoles to form and interact.

In the fourth example, NO3- (an ion) in CH3OH (a polar solvent), the dominant interparticle force would be hydrogen bonding. This is because the polar solvent molecules can interact with the charged NO3- ion through their partial charges.

In the fifth example, CH3COO- (an ion) in H2O (a polar solvent), the dominant interparticle force would also be ion-dipole interactions. This is because the polar solvent molecules can interact with the charged CH3COO- ion through their partial charges.

In general, the strength of interparticle forces can be ranked as follows: ion-ion > ion-dipole > hydrogen bonding > dipole-dipole > dispersion. It is important to consider the nature of the particles involved (polarity, charge, size, etc.) when determining the dominant interparticle force. I hope this helps clarify the concept and provides a useful guide for future problem solving.