hydrocarbons-quiz-1

Hydrocarbons Quiz-1

Dear Readers,

The one subject in NEET which is candidates who can easily attain good marks is Chemistry. That's the reason, often, one doesn’t pay notice and choose to compromise it. But if one wants to rank above others, the tip is to be thorough with NEET chemistry concepts. The understanding of reactions and definite basic understanding is what requires major attention in Chemistry but once done it only gets simpler from there. The main focus on the to-do list should be on getting a hang of the NCERT syllabus of NEET chemistry..

Q1. 

•  Alc. KOH
•  Alc. KOH followed by NaNH₂
•  Aqueous KOH followed by NaNH₂
•  Zn/CH₃ OH

Solution


 

Q2.A saturated hydrocarbon is shown by C_n H₁₀ The value of carbon atom ‘n’ in this compound is:

•  2
•  4
•  5
•  6

Solution

(b) General formula of alkane is C_n H_2n+2;2n+2=10.

Q3. Reaction of HBr with propene in presence of peroxides gives: 

•  Isopropyl bromide
•  3-bromopropane
•  Allyl bromide
•  n-propyl bromide

Solution
(d) Follow peroxide effect.

Q4. The angle strain in cyclobutane is

•  24°44'
•  29°16'
•  19°22'
•  9°44'

Solution
(d) When carbon is bonded to four other atoms, the angle between any pair of bonds =109°,28' (tetrahedral angle) but the ring of cyclobutane is square with four angles of 90°. So, deviation of the bond angle (angle strain) in cyclobutane =109°28'-(90°)⁄2 =(19°28')⁄2 =9°44'

Q5.An unsaturated hydrocarbon upon ozonolysis gives one mole each of formaldehyde, acetaldehyde and methylglyoxal(CH₃ COCHO). The structure of the hydrocarbon is

•  CH₂=CH-CH₂-CH=CH₂
•  CH₂=CH-C(CH₃ )=CH-CH₃
•  (CH₃ )₂ C=CH-CH₃
•  CH₃-CH=C(CH₃ )-CH₃

Solution
 

 

Q6. The process where straight run gasoline is cracked in order to increase octane number is called:

•  Aromatization
•  Rearrangement
•  Substitution
•  Reforming

Solution
(d) It is definition.  

Q7.What is obtained, when ammoniacal AgNO₃ reacts with acetylene?

•  Propanone
•  Silver acetylide
•  Ethylene
•  None of these

Solution

Q8.Photochemical chlorination of alkane is initiated by a process of:

•  Pyrolysis
•  Substitution
•  Homolysis
•  Peroxidation

Solution
(c) Homolysis 

Q9.Which of the following is incorrect? The members of the homologous series of alkanes?

•  Are all straight chain compounds
•  Have the general formula C_n H_2n+2
•  Show a regular gradation in physical properties
•  Have similar chemical properties

Solution

(a) Homologous may or may not be straight chain compounds.

Q10. Ozonolysis of an organic compounds gives formaldehyde as one of the products. This confirms the presence of

•  Two ethylenic double bonds
•  A vinyl group
•  An iso-propyl group
•  An acetylenic triple bond

Solution