Engineering Chemistry I Practice Test 6

1. The reaction rate is greatly influenced by ___________

It does not depend on either nature or strength of the reactant molecules

Nature of bond in the reactant molecules

Strength of bond in the reactant molecules

Both nature and strength of the reactant molecules

2. For a first order reaction, the half life period is independent of the ___________

Rate constant

Final concentration of the reactants

Initial concentration of the reactants

Concentration of products

3. Which of the following has the highest activation of the benzene ring?

– NHCOCH₃

–C₆H₅

–OH

–NH₂

4. The elementary processes with molecularity greater than ________ are not known.

5. Aromatic bromination catalyzed by the Lewis acid thalium acetate gives ___________

Ortho isomer

Meta isomer

Para isomer

Para and ortho isomer

6. The nucleophilic substitutions do not occur in haloarenes because ___________

The lone pair of electrons on the halogen participates in delocalisation with the π-electrons of benzene ring

The carbon-halogen bond is much shorter

The carbon-halogen bond is stronger compared to that in haloalkanes

All of the mentioned

7. Order of a reaction does not give any information about the reaction mechanism.

True

False

8. Which of the following is a meta directing group?

–NHCOCH₃

–COOH

–OH

–OCH₃

9. Which of the following act as catalysis in the nitration of benzene?

Dil. HCl

Conc. HCl

Conc. H₂SO₄

Dil. H₂SO₄

10. The order of the reaction, if the time of half-completion is changed from 50 sec to 25 sec, when the initial concentration is changed from 0.5 to 1M will be ___________