By which method the molecular mass of benzene was determined as 78.108 ?
Correct answer: B. Vapour density method
- A. Specific gravity method
- B. Vapour density method
- C. X-ray diffraction method
- D. Distillation methos
Explanation
Vapour density is related to molecular mass by molecular mass = 2 x vapour density when the vapour is measured relative to hydrogen. Thus a vapour density of 39.054 gives 2 x 39.054 = 78.108 g mol-1 for benzene. The likely mistake is choosing specific gravity, which compares densities of substances and is not the standard direct method for vapour molecular mass.
Last updated
About Benzene and Aromatic Compounds
Benzene has a planar ring of delocalised π electrons, giving aromatic stability and equal carbon-carbon bond lengths. The topic covers resonance, electrophilic substitution reactions such as nitration, halogenation, sulphonation and Friedel-Crafts reactions, along with substituent effects and the distinction between substitution in benzene and addition in ordinary alkenes.
Practise Chemistry of Hydrocarbons
1,091 free Chemistry of Hydrocarbons MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Chemistry questions like this
Chemistry is on 12 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
1,4-dimethylbenzene is called _.
Acetophenone can be formed by which of the following reaction for benzene?
Acetophenone can be formed by which of the following reaction of benzene?
Activation of the benzene ring in aniline can be decreased by treating with:
Among the following compounds which can be readily sulphonated: