Ethanol intermolecular forces are hydrogen bond, dipole dipole-dipole, London dispersion forces.dipole-dipole force is called hydrogen bonding.
Hello, reders welcome to another fresh article, here we will discuss about what is the intermolecular force of ethanol. you understand about ethanol intermolecular forces with proper examples.
What are the intermolecular forces of ethanol?
Ethanol intermolecular forces is a force in which it is created special class of dipole-dipole forces and hydrogen bonding, it is stronge intermolecular forces and london dispersion forces between molecules. if polar molecules interaction with other polar molecules. this type of intraction generate dipole-dipole forces. You know, ethanol is a polar molecules. interact between two polar molecules, You get as result dipole-dipole, london dispersion force and also hydrogen bonding are occur between this molecules. Mainly this types of intermolecular forces is known as dipole-dipole forces.

According to ethanol structure, hydrogen bonding (OH bonds) occur in ethanol molecules. and this intermolecular forces is called strongest intermolecular forces. this mean, ethanol has stronger intermolecular forces. it make hydrogen bond because hydrogen are bounds directly with oxygen. and it make O-H bonds. as shown in figer.

If I am talking about electronegativity of both molecules. in this case, both atoms has electronegative but oxygen is highly electronegative atoms compared with hydrogen. due to this reason, negative charge, appear on oxygen atoms whereas positive charge appear on hydrogen. they are interacted partial positive charge on one molecules (hydrogen) to partial negative charge another molecules (oxygen).
As a result, ethanol molecules form strongest intermolecular forces. this is called strongest types of intermolecular forces for example such as, hydrogen bonding, dipole dipole interaction and more. now, we will discuss the basic concepts of “hydrogen bonding“ you know that, hydrogen bonding occur if hydrogen atom are attached with highly electronegative atoms. but if electronegative atoms have,
- Small size
- loan pair
For example,
N, O & F
Where,
N – nitrogen, O – Oxygen & F – fluorine
When this type of electronegative atoms are attached with hydrogen. then hydrogen attraction electrons from electronegative atoms. It make small “sharing of electrons” between H-F , H-O and H-N. this sharing of electrons is called hydrogen bonding. hydrogen bonding is a strongest intermolecular forces compare with van der waals forces. But hydrogen bonding weaker then ionic or covalent bond.
Van der waals > hydrogen bond < ionic or covalent bond.
bond energy;
Van der waals – 8 kg/ mole
Hydrogen-bonding – 8 – 42 kg/mole
ionic or covalent bonds – 200kj/mole.
Dipole dipole interaction /forces
Yes it is true, dipole dipole forces occur between two ethanol molecules.
Here, i m talking about intraction between two ethanol molecules. there are two dipole in ethanol molecules, one dipole is carbon and another dipole is oxygen. If one dipole are interacted to another dipole, this type of intraction is know as dipole dipole intraction. In this case, carbon of ethanol molecules attract with oxygen of another methanol molecules. It is possible, because oxygen is highly electronegativity atom compared with carbon. Dut to this, positive charge appear on carbon and negative charge appear on oxygen (ie dipole-dipole). according to charge of both atoms, both atoms attract each other (positive to negative). As a results, definitely dipole dipole forces occur between carbon and oxygen. dipole dipole intraction in ethanol molecules as shown below.

where, – CH2 CH3 is a good electron donating group.
Now, we will know about dipole dipole intraction between carbon and hydrogen.

dipole dipole intraction mean, one dipole is interacted to another dipole. according to above structure, carbon is the first dipole, and oxygen is second dipole. positive charge appear on carbon (one dipole) due to electronegativity and negative charge appear on oxygen (another dipole). When one dipole intract another dipole, then, it generate, special type of forces of attraction, this is know as dipole dipole interaction.
Van der waals forces also occur between methanol molecules. you know that, when atoms or molecules are polarized a certain degree, this type of interaction are generated between atoms when interact each other.
As a result, it make intermolecular forces, such as,
- hydrogen bonds
- dipole dipole interaction
- Van der waals
This type of intermolecular forces are persent in methanol molecules.
Read More – what is the intermolecular forces of HCl?
Frequently Asked Question
1. What kind of bonding does ethanol have?
Ethanol create different type of bonding, such as
(a) bonds – H-C – non polar covalent bonds
(b) bonds – H-O & C-O are polar covalent bonds
(a) in this bonds, hydrogen are directly attachment to carbon in which it make non polar, they are weak intermolecular forces, because there are no any hydrogen bonding are persent in this bonds. So, it is no mare strongest forces.
2. In this bonds, hydrogen Or carbon are directly attached to oxygen. and as a results it is called polar molecules. because it make hydrogen bonds. If any molecules create hydrogen bonds it mean this molecules is called strongest intermolecular forces.
2. What is strongest intermolecular forces in Acetone?
Acetone molecules have weak intermolecular forces. that is called dispersion forces. acetone molecules are attraction by London dispersion forces and dipole dipole interaction.
this molecules has dipole, so it is create dipole dipole forces. there is no hydrogen bonding because hydrogen bonding is not directly attachment to oxygen. So, if this molecules has no hydrogen bonding it will be weak intermolecular forces.
3. Why acetone create weak intermolecular forces?
Yes it is true, Acetone has weak intermolecular forces because there is no hydrogen bonding persent in this molecules. So it create weak intermolecular forces. if any molecules has no hydrogen bonding. So, it indicate weakest intermolecular forces.
but if i m talking about Water molecules this molecules create hydrogen bonding. because hydrogen are attached to oxygen. and hydrogen have positive charge and oxygen have negative charge. it attack properly. as a result, it give strongest intermolecular forces.
4. Which of the following exhibits the weakest intermolecular forces?
(a) nh3
(b) H2O
(c) CH3OH
(d) He, Cl2
According to above option, option (d) is correct answer.
Because, He and Cl2 exist weakest intermolecular forces (London dispersion forces).
This type of molecules (He, Cl2) is non polar that why it have weakest intermolecular forces. and other molecules such as (nh3, H2O, and HCl) this type of molecules creat hydrogen bond. This mean it creat stronger intermolecular forces.
so, we can say that, option (d) is correct.
5. Is acetone more polar then ethanol?
Yes it is true that Acetone has less polar then ethanol. But if I m talking about dipole movment, then acetone has more dipole dipole interaction (dipole movment) compare then ethanol.