ORGANIC CHEMISTRY - SOME BASIC PRINCIPLES AND TECHNIQUES Quiz-16

Organic chemistry - some basic principles and techniques Quiz-16

Dear Readers,

IIT JEE exam which consists of JEE Main and JEE Advanced is one of the most important entrance exams for engineering aspirants. The exam is held for candidates who are aspiring to pursue a career in the field of engineering and technical studies. Chemistry is important because everything you do is chemistry! Even your body is made of chemicals. Chemical reactions occur when you breathe, eat, or just sit there reading. All matter is made of chemicals, so the importance of chemistry is that it's the study of everything..

Q1.Which of the following species is most stable?

•  
•  
•  
•  

Solution
Benzyl radical is more stable than 3° radical

Q2.The number of isomers for the compound with molecular formula C_2 BrClFI is:

•  3
•  4
•  5
•  6

Solution
/

Q3. 0.24 gm of a volatile liquid upon vaporisation gives 45 ml of vapours at STP. What will be the vapour density of the substance? (Density of H_2 = 0.089 gm litre^(-1))

•  9.539
•  59.93
•  5.993
•  95.39

Solution
/

Q4. 0.3 gm of platinichloride of an organic diacidic base left 0.09 gm of platinum on ignition. The molecular weight of the organic base is:

•  120
•  240
•  180
•  60

Solution
/

Q5. The compound which is not isomeric with diethyl ether is:

•  n-Propyl methyl ether
•  Butan-1-ol
•  2-Methyl propan-2-ol
•  Butanone

Solution
 Ethers and alcohols are functional isomers, so butanone (ketone) is not isomeric with diethylether

Q6. The total number of cyclic isomers possible for a hydrocarbon with the molecular formula C_4 H_6 is

•  1
•  3
• 5
•  7

Solution
/

Q7. The decreasing nucleophilicity of the following is:/

•  IV>III>II>I
•  I>II>III>IV
•  IV>III>I>II
•  II>I>III>IV

Solution
Acidity as explained in (a) is : CH_3 SH>CH_3 OH>H_2 O>EtOH When nucleophilic centre is different and they belong to the same group, nucleophilicityantiparallels basicity∴ nucleophilicity: ,so the answer is (c)

Q8. The nodal plane in the π-bond of ethane is located in:

•  The molecular plane
•  TA plane parallel to the molecular plane
•  A plane perpendicular to the molecular plane which bisects the carbon-carbon σ-bond at right angle
•  A plane perpendicular to the molecular plane which contains the carbon-carbon σ-bond

Solution

/

Q9. Pure enantiomericacid+optically active alcohol having chiral C atom →? The product will be:

•  An optically active compound
•  A meso compound
•  A racemic mixture
•  A pure enantiomer

Solution
(+)RCOOH + (-) R^' OH→ (+)(-)RCOOR' Pure enantiomeric acid (O.A. alcohol) (O.A. ester)

Q10. Insulin contains 3.4% sulphur. The minimum molecular mass of an insulin is:

•  940
•  350
•  470
• 560

Solution
3.4 gm S is in 100 gm of compound 32 gm of S is in (100×32)/3.4=941.7≈940