Organic Chemistry Interview Questions & Answers

Question 1. Trimethylamine Is A Pyramidal Molecule. What Is The Hybridization At Nitrogen?

Answer :

The nitrogen is bonded to three CH3 groups and has a lone pair, so the hybridisation is sp3.

Question 2. How Many Stereoisomers Of Phenylpropylene Oxide Are There?

Answer :

Two positional isomer A and B & two Stereoisomer of each so, total 4 isomers.

Question 3. Which One Of The Following Is Not Aromatic? 1)cyclotetrane 2)benzene 3)napthalene 4)anthracene ?

Answer :

cyclotetrane, because of the double bonds are not conjugation

Question 4. Number Of Sigma Bonds Present In Benzene Are Same As ..?

Answer :

Number of Sigma bonds present in Benzene are same as Borazine (inorganic Benzene).

no. of sigma bonds in Benzene= 12 (C6H6)
no. of sigma bonds in Borazine= 12 (B3N3H6)

Question 5. The Name Benzene Was Proposed By?

Answer :

Kekule

Question 6. Which Is Useful In The Manufacture Of Insectisides?

Answer :

Rotenone, Azadirachtin are natural insecticides, synthetic routes are deveoped recently.

DDT, Gammaxene were used but were scraped out as they pose health hazards and are insects are able sustain the max. dosages every year. Generally, Semio-chemicals, a class of compounds found in insects themselves are being studied and used as effective insecticides and warfare agents.

Question 7. What Are The 4 Classes Of Unsaturated Fatty Acids?

Answer :

1. Monounsaturated fat: This is a type of fat found in a variety of foods and oils.
2. Polyunsaturated fat: This is a type of fat found in plant-based foods and oils.They can be divided into two groups known as omega-3 fats and omega-6 fats. 
3. Omega-3 fatty acids: One type of polyunsaturated fat made up of mainly omega-3 fatty acids and may be beneficial to heart.
4. Omega-6 fats decrease risk of heart disease when they are consumed in place of saturated and trans fats.

Question 8. What Is The Difference Between Coordinate Covalent Bond And Covalent Bond?

Answer :

IN coordinate covalent bond electrons which are shared by both the atoms are comtributed by only one atom . This is otherwise known as dative bond. 

In covalent bond the electrons shared by both the atoms are contributed by both the atoms equally.

Question 9. What Happens When Aminoacids React With Alcohols?

Answer :

when alcohols reats with aminoacids esters are formed. The esters are volatile in contrast to free aminoacids.

R-CH-COOH + H2O-C2H5 -> R-CH-COO-C2H5 + H2O
NH2 NH2

Question 10. What Are Ligases?which Type Of Reactions They Will Catalyse?

Answer :

Ligases are the group of enzymes that catalyse the transfer of a group from one kind of molecule to another. These are also called transferases.

Question 11. Nh2-ch2-cooh Belongs To What Structure?

Answer :

its the structure of amino acid glacine

Question 12. Mention The Factors Affecting Solubility Of Compounds?

Answer :

temperature, pH, structure of compound i.e., whether the compd is straight chain or branched & molecular weight of compd.

Question 13. What Are Geometrical Isomerism? Explain Them With An Example?

Answer :

Geometrical isomerism is an example of stereo-isomerism. 

This occurs when substances have the same molecular formula, but a different arrangment of their atoms in space. There are three ways that this can happen: 

where there is a C=C bond in the molecule; 
where a molecule has rings; or 
where there is a >C=N bond.

Question 14. How 'salting Out' Process Is Used In Extraction?

Answer :

Proteins are precipitated from aqueous solution by high concentrations of neutral salts. This is the"salting -out" process.

Divalent and trivalent ions are more effective than univalent ions.

The salts commonly used for this purpose are NA2SO4,(NH4) 2SO4 Magnesium salts, and phosphates.

Question 15. What Is Saponification Of Oils?

Answer :

When fats are hydrolysed with alkhali,the free fatty acids react with alkali to form metallic acids.these salts are soaps and this process is called saponification.

Question 16. What Is Redox Potential Of An Organic Compound?

Answer :

The quantitative measure of the affinity of a compound to lose or gain electrons is the redox potential.

Question 17. What Is Lithipone?

Answer :

Lithipone is a white pigment.it is amixture of BaSO4&ZnS.

Question 18. What Is Difference Between Anti-aromatic And Non-aromatic Compounds?

Answer :

Anti aromatic compounds follows 4npi electron rule and are cyclic compounds, planar, where as non aromatic are non planar or planar, cyclic or acyclic.

Question 19. What Is The Range Of Uv & Vis Lamp In Spectrophotometer?

Answer :

• uv lamp range is 200 nm to 340 nm. 
• vis lamp range is 320 nm to 1100 nm. 

both of lamp range is mfg instument company voice of record is enculd the data range in lamp is 200 nm to 1200 nm.

Question 20. If Benzene And Tolune Both Can Be Mixed... What Is The Boiling Point For The Mixture And Its Density?

Answer :

If benzene and toluene mixed the boiling point will be ~ 90oC. Density will not change.

Question 21. Benzoic Acid Is A Weaker Than Para Nitro Benzoic Acid?

Answer :

in p-nitrobenzoic acid due to -I effect of nitro group hydrogen present in acia become more elecronegative and easily remove as proton and act like strong acid.

Question 22. What Is The Difference Between Sulphated Ash And Roi?

Answer :

There no difference between procedure, both are same. we generally term it as sulphated ash test/roi.in indian pharmacoepia, called it as roi and in usp, called it as sulphated ash tesh. both are used for the determination of content of inorganic matter in an organic substance.

Question 23. If Tis Below Reaction Does Happaen Means...,what Is The End Product.......? Naphthal + Toluene(or)benzene?

Answer :

high molecular weight easily we can seperate koH

Question 24. What Is The Difference Between Pvc And Upvc Plastic?

Answer :

PVC-POLYVINYL CHLORIDE AND uPVC IS THE Unplasticized polyvinyl chloride IT IS USED FOR building industry as a low-maintenance material.

Question 25. What Mean By Organic Chemistry?

Answer :

Organic Chemistry is a branch of Science, which deals study about carbon compounds except Carbon monoxide, Carbon di oxide and corbonates.

Question 26. Which Organic Compound Is Used As A Fuel In Jet Air Crafts? A. 100 Octane B. 90 Octane C. Kerosine Oil D. Diesel Oil

Answer :

Kerosine oil

Question 27. What Is The Difference Between An Ion And A Radical?

Answer :

An ion is a specie that have no unpaired electron and is charged, either positively or negatively i.e. may be a cation or an anion. It is formed due to heterolysis of a molecule

e.g HCl----> H+ + Cl- 

A radical is a neutral specie having atleast one unpaired electron and is formed due to homolysis of a molecule

e.g H-H -------> H* + H* 

The * shows an unpaired electron. Similarly CH3* is a radical.

Question 28. How To Synthsis Toluene To Benzaldehyde?

Answer :

from directly reaction of toluene to cromyl chloride (CrO2Cl2) at room temp. to form benzaldehyde.

Question 29. How To Make A 100ml Solution With Given 10gm Of Naoh?

Answer :

Take 100ml water and pore 10gr NaOH pellets sterr with gently boil. NaOH sol ready.

Question 30. How We Can Differentiate Between Oxalic Acid And Tartaric Acid?

Answer :

By Fluorescein test ... where tartaric acid " used in baking powder and found  in many food products 

oxalic acid : harmful in contact with skin or eyes  toxic .remove Ca ions From blood and also block Kidneys  Fluoresce in test depended on Light passes & usually in UV light