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Chemisorption involves formation of bond...

Chemisorption involves formation of bond between gaseous molecules or atoms and the solid surface for which high energy is required. Thus it is also referred as

A

Chemical adsorption

B

positive adsorption

C

activated adsorption

D

passive adsorption

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To solve the question regarding chemisorption, we need to analyze the key concepts related to adsorption and the specific characteristics of chemisorption. ### Step-by-Step Solution: 1. **Understanding Adsorption**: - Adsorption is the process where atoms, ions, or molecules from a gas, liquid, or dissolved solid adhere to a surface. This is a surface phenomenon. 2. **Types of Adsorption**: - There are two main types of adsorption: - **Physisorption**: This involves weak van der Waals forces and does not involve any significant energy change. - **Chemisorption**: This involves the formation of strong chemical bonds between the adsorbate (the substance being adsorbed) and the adsorbent (the surface). 3. **Characteristics of Chemisorption**: - Chemisorption is characterized by: - The formation of a chemical bond. - A significant amount of energy is required for this bond formation, which is why it is considered to have a high activation energy. 4. **Terminology**: - Due to the high energy requirement for the formation of chemical bonds in chemisorption, it is often referred to as **"activated adsorption"**. 5. **Conclusion**: - Thus, the correct answer to the question is that chemisorption is also referred to as **activated adsorption**. ### Final Answer: Chemisorption is also referred to as **activated adsorption**.
To solve the question regarding chemisorption, we need to analyze the key concepts related to adsorption and the specific characteristics of chemisorption. ### Step-by-Step Solution: 1. **Understanding Adsorption**: - Adsorption is the process where atoms, ions, or molecules from a gas, liquid, or dissolved solid adhere to a surface. This is a surface phenomenon. 2. **Types of Adsorption**: ...
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The force of interaction between the molecules of same substance is called cohesive force hile force of interaction between molecules of different substances is called adhesive force . Both the forces are attracive and have a range of about 10 A . If we consider a molecule . A well inside a liquid we find that it is equally attracted by the surrounding molecules in all the dirctions ( with a sphere of radius 10 Å ) and so it does not experience any resultant force . On or near the surface of a liquid , the molecules do not exist on the free side and so a molecule ( say B ) experiences a resultant force vertically downwards into the liquid . For this reason , the molecules of the surface have a tendency to go into the liquid . Thus , the surface tends to contract and gives rise to surface tension . As surface molecules like B experience a net downward force of cohension and have tendency to go down , so in increasing the area of the surface more molecules are to be shifted to the surface from inside . Thus , more mechnical work will have to be done against the net downward force of cohension . This work is stored by the molecules in the surfaces as potential energy called free surface energy . Furthermore , molcules like P , in contact with the liquid will stick to the solid surface , i.e will meet it if the force of adhesion A is greater than net force of cohension C . The liquid will not the solid surface if C gt A Also , molecules like Q at the surface in contact with the solid will experience a net force of cohension C_(R) . If adhesion A is greater then cohension C_(R) , the resultant force will be F . As the liquid can't support tangential force , F must be perpendicular to the surface of the liquid . So , the menisus will be concave and the angle of contact will be acute ( gt 90^(@)) . However , if adhesion is lesser than cohension , the resultant force F will be directed into the liquid and so the menisus ( which is perpendicular to F as liquid support tangential force ) will be convex and the angle of contact will be obtuse ( gt 90^(@)) The free suface energy , stored in the surface is because of work done

The force of interaction between the molecules of same substance is called cohesive force hile force of interaction between molecules of different substances is called adhesive force . Both the forces are attracive and have a range of about 10 A . If we consider a molecule . A well inside a liquid we find that it is equally attracted by the surrounding molecules in all the directions ( with a sphere of radius 10 Å ) and so it does not experience any resultant force . On or near the surface of a liquid , the molecules do not exist on the free side and so a molecule ( say B ) experiences a resultant force vertically downwards into the liquid . For this reason , the molecules of the surface have a tendency to go into the liquid . Thus , the surface tends to contract and gives rise to surface tension . As surface molecules like B experience a net downward force of cohension and have tendency to go down , so in increasing the area of the surface more molecules are to be shifted to the surface from inside . Thus , more mechnical work will have to be done against the net downward force of cohension . This work is stored by the molecules in the surfaces as potential energy called free surface energy . Furthermore , molcules like P , in contact with the liquid will stick to the solid surface , i.e will meet it if the force of adhesion A is greater than net force of cohension C . The liquid will not the solid surface if C gt A Also , molecules like Q at the surface in contact with the solid will experience a net force of cohension C_(R) . If adhesion A is greater then cohension C_(R) , the resultant force will be F . As the liquid can't support tangential force , F must be perpendicular to the surface of the liquid . So , the menisus will be concave and the angle of contact will be acute ( gt 90^(@)) . However , if adhesion is lesser than cohension , the resultant force F will be directed into the liquid and so the menisus ( which is perpendicular to F as liquid support tangential force ) will be convex and the angle of contact will be obtuse ( gt 90^(@)) A liquid particle B , which is present in the vicinity particle A can exert a force on A if the distance of B from A is

L.C.A.O. Principle is involved in the formation of the molecular orbitals according to molecular orbital theory. The energy of the bonding molecular orbital is less than that of the combining atomic orbitals while that of the antibonding molecular orbitals while that of the order (B.O.)=1/2(N_(b)-N_(a)) helps in predicting (i) formation of molecules/molecular ions, bond dissociation energy, stability and bond length. Only the molecules or ions with positive B.O. can be formed. These will be diamagnetic if all molecular orbitals are dilled and paramagnetic if one of more are half filled. The atomic orbitals at the time of overlap must have the same symmetry as well. The bond order (B.O.) in B_(2) molecule is:

L.C.A.O. Principle is involved in the formation of the molecular orbitals according to molecular orbital theory. The energy of the bonding molecular orbital is less than that of the combining atomic orbitals while that of the antibonding molecular orbitals while that of the order (B.O.)=1/2(N_(b)-N_(a)) helps in predicting (i) formation of molecules/molecular ions, bond dissociation energy, stability and bond length. Only the molecules or ions with positive B.O. can be formed. These will be diamagnetic if all molecular orbitals are dilled and paramagnetic if one of more are half filled. The atomic orbitals at the time of overlap must have the same symmetry as well. In the homonuclear molecule which of the following sets of M.O. orbitals are degenerate ?

L.C.A.O. Principle is involved in the formation of the molecular orbitals according to molecular orbital theory. The energy of the bonding molecular orbital is less than that of the combining atomic orbitals while that of the antibonding molecular orbitals while that of the order (B.O.)=1/2(N_(b)-N_(a)) helps in predicting formation of molecules/molecular ions, bond dissociation energy, stability and bond length. Only the molecules or ions with positive B.O. can be formed. These will be diamagnetic if all molecular orbitals are dilled and paramagnetic if one of more are half filled. The atomic orbitals at the time of overlap must have the same symmetry as well. In the formation of N_(2)^(+) from N_(2), the electron is removed from a

L.C.A.O. Principle is involved in the formationof the molecular orbitals according ot molecular orbital theory. The energy of the bonding molecular orbital is less than that of thecombining atomic orbitals while that of the antibonding molecular orbitals while that of the order (B.O.)=1/2(N_(b)-N_(a)) helps in predicting (i) formation of molecules/molecular ions, bond dossociation energy, stability and bond length. Only the molecules or ions with positive B.O. can be formed. These will be diamagnetic if all molecular orbitals are dilled and paramagnetic if one of more are half filled. The atomic prbitals at the time of overlap must have the same symmetry as well. Bond arder is :

Most of the polyatomic molecules except a few such as CO_(2) and CS_(2) are linear or angular with a bond angle generally somewhat greater than 90^(@) A bond angle is defined as the angle between the direction of two covalent bonds Since the atoms in molecules are in constant motion with respect to each other they are not expected to have a fixed value of bond angle Repulsion between non-bonded atoms alone does not provide an adequate explanation Hybridisation of bonding orbitals an adequate explanation Hybridisation of bonding orbitals also plays a very important role in detrmining the value of bond angle It has been observed that in hybridisation as the s-character of hybrid orbital increases the bond angle increases In P_(4) molecule phosphorous atoms are tetrahedrally arranged The angle P-P-P in the molecule is .

L.C.A.O. principle is involved in the formation of molecular orbitals according to molecular obtital theory. The energy of bonding molecular orbital is less than that of the combining atomic orbitals while that of the anitibonding bonding melecular orbital is more. The B.O. =^(1//2)[N_(b)-N_(a)] Answer the following questions on the basis of the above paragraph : (i) What is bonding molecular orbital ? (ii) Calculate B.O. of He_(2) molecule.

Adsorption is the tendency of accumulation of molecular species at the surface of solid or liquid. Depending upon the nature of bonds or forces of attraction between adsorbate and adsorbent. It is classofied between physisorption and chemisorption. Which of the following gases is adsorbed most by activated charcoal?

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