Which of the following exhibits the weakest intermolecular forces?

Hello, reders i am going to explain about which of the following exhibits weakest intermolecular forces.

Which of the following exhibits the weakest intermolecular forces – actually, the exact answer of this question is helium.

lets know in details,

Read More – Which type of intermolecular forces exist in Cl2 and CCl4?

Which of the following exhibits the weakest intermolecular forces?

1. NH3

2. CH2OH

3. HCl

4. He

The option 4 is correct but why?

lets know in details with examples about why option 4 is correct?

1. NH3

In ammonia molecules, Ammonia (NH3) exist three different type of intermolecular forces. such as, hydrogen bond, dipole dipole interaction, and london dispersion forces.

There are three type of intermolecular forces occur in nh3 molecules, they are, hydrogen bonding, dipole dipole interaction and london dispersion forces,

Here, i m going to explain in details for both intermolecular forces.

hydrogen bonding,

Yes, hydrogen bonding occur between nh3 molecules because according to the structure, hydrogen are directly attached with high electronegative atom such as nitrogen (N). we know that, if any molecules bound to highly electronegative elements then they generate hydrogen bonds between two molecules such as, N-H, H-O, and H-F then it makes hydrogen bond between molecules. due to large difference of electronegativity. negative charge is appear on nitrogen and positive charge is appear on hydrogen. due to this both atoms are attract each other. and According to this attraction, hydrogen bonds are generated between molecules.

According to difference in electronegativity between two atoms., suc as, N and H. you know that, the value of electronegative of nitrogen is 3.0 and the value electronegative of hydrogen is 2.2. it mean nitrogen has highly electronegative atoms compare with hydrogen. the difference of electronegativity between atoms is (0.8). therefore, the large difference in electronegativity between the N atom and H atom, N-O, N-F atoms leads to highly polar covalent bond. so, you can say that, polar molecules generated hydrogen bonding.

As a result, this molecules is called highly polarized molecules. in this case, partial positive charge appear on hydrogen and partial negative chare appear on nitrogen. there are two highly polarized molecules. and both are attract each other. partial positive charge of hydrogen are attracted with partial negative charge of other molecules. As a result attraction forces is produced between them. this type of forces is called hydrogen bonding. hydrogen bonding is also called intermolecular forces between two molecules.

Dipole dipole interaction

Dipole-dipole intraction are attracted among polarized molecules. we know that polarized molecules has two poles partial positive pole and partial negative pole. therefore it is called dipole. dipole dipole intraction occur between two polarized molecules or between two polarized dipole.

If we are taking about one dipole, it has two pole partial positive pole and partial negative poles. consider another dipole it has also two poles, partial positive pole and partial negative poles, we has two dipoles. So, if we are talking about nh3 molecules, it has two pole, one is negative pole and another is positive pole, the negative pole of one molecules attracted the positive pole of another molecules. due to this attractive forces are produces. this attractive forces is called dipole dipole intraction.

london dispersion forces

If molecules overall is non polar then it is only intermolecular forces is the london dispersion forces. as you will remember this(LDF) is the weakest intermolecular forces.

You know, london dispersion forces is not operate long distance, it is oprate short distance. it creat temporary positive to temporary negative charged. London dispersion forces is a weak force compare with dipole-dipole intraction.

According to above discussion, NH3 molecules are not a weakest intermolecular forces.

2. CH3OH

Yes, hydrogen bonding is present between two methanol molecules. because oxygen is directly attached to hydrogen and due to this hydrogen bonding, it is strong intermolecular forces occur between oxygen and hydrogen. You know that oxygen is highly electronegativity atoms compare with hydrogen. due to this, oxygen has partial negative charge whereas hydrogen has partial positive charge. according to this both atoms are attracted each other.

As a results hydrogen bonding occur between this two molecule. You can understand properly with the help of chemical structure.

Dipole dipole forces

Yes, dipole-dipole interaction occur in methanol because it creat dipole moment between molecules due to the presence of the electronegative oxygen atom. electronegative atom which is oxygen that create a permanent positive charge on the molecules and rest of the molecules create partial positive. that create parmanent dipole within each of the methanol molecules with opposing charge. this type of interaction is called dipole-dipole interaction.

London dispersion forces

Yes, it is absolutely true, methanol are also generate london dispersion forces between two non polar molecules. basic concepts is this that the interaction between two non polar methanol molecules. it mean, one hydrogen atom of first methanol interacted with second hydrogen of second methanol molecules. But It generated very weak intermolecular forces. In other words, there is a one type of interaction between two methanol molecules in which very weak intermolecular forces are generated. and this weak interaction is know as London dispersion forces.

According to this, this molecules has hydrogen bonding (stronger intermolecular forces) so, we can say that this molecules is not weakest intermolecular forces.

3. HCl

HCl are made “polar covalent bonds” when atoms share electrons between hydrogen and chloride. Polar covalent bonds atoms such as hydrogen and chloride.

HCl is made covalent bonds not hydrogen bonds. Because covalent bonds made in the presence of sharing of electrons between hydrogen and chloride. hydrogen bonds are made if hydrogen are bound to strong electronegative elements such as, Nitrogen, oxygen, fluoride. but HCl intermolecular forces has dipole dipole interaction and London dispersion forces. You know that, Cl is highly electronegative atoms compare with hydrogen. thats why, partial negative charge are appear on Cl and partial positive charge appear on hydrogen.

According to this, both atoms interact each other and it generated dipole dipole forces and London dispersion forces. the hcl intermolecular forces are dipole dipole intraction, because it is a polar molecules. the dipole dipole interaction are more attracted on polar molecules. it is one type of strongest intermolecular forces of attraction.

intermolecular forces in hydrogen chloride are made as intermolecular hydrogen bonding. it is occur if H (hydrogen) is bound to strongly electronegative elements. nitrogen and oxygen is a one type of strongest electronegative elements. If it is bound to (N) nitrogen or (O) oxygen then it make hydrogen bonding otherwise it can’t be made hydrogen bonding.

finely, we can say that, covalent bond, dipole dipole interaction and London dispersion forces exist in HCl molecules.

This mean, HCl exist strong intermolecular forces not weak intermolecular forces.

4. He

Helium is one type of noble gas elements. helium has no any attractive forces. this mean, there are no any attractive forces exist in helium.

london dispersion forces occur in helium. there is no any other intermolecular forces occur. because there is no any dipole for attractions. there is no create any negative pole Or positive pole. there is no interaction each other (between two dipole) this mean, it is called LDF. So, we can say that london dispersion forces occur in He.km

According to above discussion, we can say that this type molecules exist weakest intermolecular forces.

If i m talking about chlorine molecules, you know, this molecules is a non polar molecules. in nonpolar molecules, it exist only london dispersion forces. this forces is called as a weakest intermolecular forces.

London dispersion forces is a temporary dipole. this mean, it is work as temporary dipole in molecules. it can occur in non polar molecules. Induced a dipole in neighboring molecules. there is no any dipole to attract each other. this mean, in any non polar molecules has no any dipole, this is the reason it not attract each other properly.

According to above discussion, we can say that this type molecules exist weakest intermolecular forces.

If we are talking about carbon tetrachloride,this type of molecules overall is non polar then it is only intermolecular forces is the london dispersion forces. london dispersion forces is not operate long distance, it is oprate short distance. it creat temporary positive to temporary negative charged. london dispersion forces is a weak force compare with dipole-dipole intraction.

There is no any dipole to attract each other. this mean, in any non polar molecules has no any dipole, this is the reason it not attract each other properly. london dispersion forces which is the weakest intermolecular forces compare with hydrogen bond and dipole dipole intraction.

According to above discussion the answer of this question, which of the following exhibits the weakest intermolecular forces, is He (helium)

Because helium molecules exist weakest intermolecular forces.

So, option 4 is correct.