1. Which of the following is the simplest member of organic compounds?
a) Formic acid
Explanation: Methane is the simplest member of the alkane family and indeed the simplest of organic compounds, as all other compounds are derived by altering this compound.
2. Which of the following is the known name for the reaction given below?
(where, X=Cl, Br, I, OTf; R2=Alkyl, aryl, H; R3=alkyl, aryl)
a) Ullmann reaction
b) Gabriel phthalimide synthesis
c) Buchwald-Hartwig Reaction
d) Chan-Lam coupling
Explanation: The Buchwald–Hartwig amination is a chemical reaction used in organic chemistry for the synthesis of carbon–nitrogen bonds via the palladium-catalyzed cross-coupling of amines with aryl halides.
3. Which of the following is yielded when Ethylene glycol is treated with phosphorus tri-iodide?
a) ethylene di-iodide
d) ethyl iodide
Explanation: Phosphorus triiodide (PI3) is an unstable red solid which reacts violently with water. It is a common misconception that PI3 is too unstable to be stored; it is, in fact, commercially available. It is widely used in organic chemistry for converting alcohols to alkyl iodides.
4. Hydrocarbons are organic compounds with element __________
a) Both hydrogen and carbon
Explanation: These organic compounds are made up of only carbon and hydrogen and hence the name hydrocarbons.
5. Which of the following bond is made up of a large number of organic compounds?
a) Metallic bond
b) Dipolar bond
c) Ionic bond
d) Covalent bond
Explanation: This is because they have the tendency to transfer electrons.
6. Which of the following is a classification of Organic compounds?
a) alicyclic compounds and acyclic compounds
b) Cyclic compounds and alicyclic compounds
c) Open chain compounds and acyclic compounds
d) Open chain compounds and linear chain compounds
Explanation: Organic compounds are broadly classified into open chain and closed chain compounds.
7. Which of the following is not a class of organic compounds?
b) Electro compounds
c) Nitro compound
d) Carbonyl compound
Explanation: Classes of organic compounds are those which involves organic compounds such as carbon, hydrogen and oxygen. Hence, electro compounds is not a class of organic compounds.
8. Organic compounds can be classified even based upon the function groups. Which of the following is not a functional group?
Explanation: Isocyanide is a compound and it is not a functional group.
9. Which of the following does not come under the organic addition reaction?
Explanation: Dehydration comes under elimination reaction and hence it does not come under addition reaction.
10. Which of the following organic compound with molecular formula C3H C12 exhibits only one signal in the IH NMR spectrum?
a) 1, 2-dichloropropane
b) 1, 1-dichloropropane
c) 2, 2-dichloropropane
d) 1, 3-dichloropropane
Explanation: Only (a) compound has all chemically equivalent hydrogen. So, give only one peak.organic-chemistry-questions-answers-nuclear-magnetic-resonance-1-q1
11. Which of the following is an organic compound having the molecular formulae C10H14 exhibited two singlets in the 1H NMR spectrum and three signals in the 13C NMR?
Explanation: In compound a;
Here only 2 types of Hydrogen are present (two Ha & twelve Hb). So, 2 singlets only. There is no need to check 13C NMR. Still, if you check three types carbon are present (two C1, four C2 and four C2 carbon). Hence, there peak for 13C NMR.
12. An organic compound (MF; C8H10O) exhibited the following 1H NMR special data: 62.5 (3H, s), 3.8 (314, s), 6.8 (2H, d, J 8 Hz), 7.2 (2H, d, J 8 Hz) ppm. Which of the following is that compound among the choices?
a) 4-methylbenzyl alcohol
b) 4-methyl anisole
3Ha –> 3.8, singlet (deshielded because of –I of oxygen)
3Hb –> 2.5, singlet (No such –I)
2Hc –> 7.2, doublet (deshielded because of anisotropy effect of benzene as well as because of –I of oxygen)
2Hd –> 6.8, doublet (deshielded because of anisotropy of benzene).
13. Which of the following complex is in which organic ligand is having only bond with metal?
Explanation: CH3 is the only σ-donor ligand while C2H4, C5H5, C6H6 are π-acceptor ligands.
14. Which of the following statement is not true about ethers?
a) Lower ethers also act as anaesthetics
b) Simple ethers (such as diethyl ether) are tasteless
c) The lower ethers are highly volatile and flammable
d) Ethers are not organic solvents
Explanation: Because like dissolve like, Diethyl ether is very non-polar compared to water so it will dissolve the non-polar substances and precipitate the ionic compounds. Since like dissolves like, your barely-polar organic ether is often happy to dissolve your non-polar organic molecules.
15. An organic compound A reacts with sodium metal and forms B. On heating with conc. H2SO4, A gives diethyl ether. What are A and B?
a) C4H9OH and C4H9ONa
b) CH3OH and CH3ONa
c) C2H5OH and C2H5ONa
d) C3H7OH and CH3ONa
Explanation: When C2H5OH reacts with sodium metal and forms C2H5ONa and on heating with H2SO4 giver diethyl ether.