Blog

13. Which of the following nitrogen oxides do not contain N#N bonds? a. N2O5 b. N2O4 c. N2O d. all of the above The correct answer is d. all of the […]

12. Which of the following dienes does not react with the dienophile in the Diels-Alder reaction? a. A b. B c. C d. D The diene that does not react […]

11. A transition is spectroscopically allowed if it obeys: a. Wien’s displacement law b. The law of conservation of energy only c. The law of conservation of angular momentum only […]

10. A dye that is non-fluorescent in water becomes fluorescent with an emission maximum at 430 nm when bound to a globular protein. Its absorption maximum is 400 nm. Given […]

9. Proton NMR of ethyl acetate will show a. Three peaks, singlet-doublet-triplet in 3:2:3 intensity ratio b. Three peaks, singlet-quartet-triplet in 3:2:3 intensity ratio c. Three peaks, doublet-quartet-triplet in 2:2:3 […]

8. Which conformation of cyclohexane has a C3 axis of symmetry? a. Boat b. Twist boat c. Chair d. Envelope The chair conformation of cyclohexane possesses a C3 axis of […]

7. Nucleophilic attack will be most facile on a. CH2=CF2 b. CH2=CCl2 c. CF2=CF2 d. CH2=CH2 Nucleophilic Attack on Alkenes: CH2=CF2 Most Facile Nucleophilic attack occurs most readily on CH2=CF2 […]

6. The correct shape of the [TeF5]– ion on the basis of VSEPR theory is a. trigonal bipyramidal b. square pyramidal c. pentagonal planar d. see-saw The correct shape of […]

5. In an enzyme-catalysed reaction, if [S] = 10 KM the velocity of the reaction is about: a. 0.9 Vmax b. 0.7 Vmax c. 0.5 Vmax d. 0.1 Vmax Introduction […]

4. What type of impurity atoms are used to increase the number of conduction band electrons in intrinsic silicon? a. bivalent b. trivalent c. tetravalent d. pentavalent Pentavalent Impurity Atoms […]