1.The reaction of propone with HOCl (Cl2 + H2O) proceeds through the intermediate. A) $CH_{3}-CH-CH_{2}-Cl$ B) $CH_{3}-CH(OH)-CH_{2}$ C) $CH_{3}-CHCl-CH_{2}$ D) $CH_{3}-CH-CH_{2}-OH$ View Answer Report DiscussAnswer: Option AExplanation:
2.In the Hofmann-bromamide degradation reaction, the number of moles of NaOH and Br2 used Per mole of amine produce are A) 4 moles of NaOH and 2 moles of $Br_{2}$ B) 2 moles of NaOH and 2 moles of $Br_{2}$ C) 4 moles of NaOH and 1 mole of $Br_{2}$ D) 1 mole of NaOH and 1 mole of $Br_{2}$ View Answer Report DiscussAnswer: Option CExplanation:Hofmann-bromamide degradation reaction is given as: $RCONH_{2}$ + $4NaOH$ + $Br_{2}$ $\rightarrow$ $RNH_{2}$ + $Na_{2}CO_{3}$ + $2NaBr$ + $2H_{2}O$ Hence, four moles of NaOH and one mole of are used.
3.The reaction of zinc with dilute and concentrated nitric acid, respectively, produce A) $NO_{2}$ and $NO$ B) $NO$ and $N_{2}O$ C) $NO_{2}$ and $N_{2}O$ D) $N_{2}O$ and $NO_{2}$ View Answer Report DiscussAnswer: Option DExplanation:$Zn$ + $4HNO_{3} (conc)\rightarrow$ $Zn (NO_{3})_{2}$ + $2H_{2}O$ + $2NO_{2}$ $4Zn$ + $ 10HNO_{3}\rightarrow$ $4Zn(NO_{3})_{2}$ +$N_{2}O$ + $5H_{2}O$
4.Which of the following atoms has the highest first ionization energy? A) Na B) K C) Sc D) Rb View Answer Report DiscussAnswer: Option CExplanation:Order of first ionization energy is Sc > Na>K>Rb. Due to poor shielding effect, removal of one electron from 4s orbital is difficult as compared to 3s-orbital.
5.Which one of the following complexes shows optical isomerism? A) $cis[Co(en)_{2}Cl_{2}]Cl$ B) $trans[Co(en)_{2}Cl_{2}]Cl$ C) $[Co(NH_{3})_{4}Cl_{2}]Cl$ D) $[Co(NH_{3})_{3}Cl_{3}]$ View Answer Report DiscussAnswer: Option AExplanation: $[Co(NH_{3})_{4}Cl_{2}]Cl$ can exist both in cis and trans forms that are given below $[Co(NH_{3})_{3}Cl_{3}]$ exists in fac and mer-isomeric forms and both are optically inactive.