Identify the alkyne in the following sequence of reactions,Alkyne

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 Multiple Choice QuestionsMultiple Choice Questions

91.

Which of the following is an example of interstitial hydride?

  • NH3

  • CH4

  • ZnH2

  • H2O


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92.

Identify the alkyne in the following sequence of reactions,

Alkyne Lindlar's catalystH2 A Ozonolysis B Wacker process CH2=CH2

  • H3C-C≡C-CH3

  • H3C-CH2-C≡CH

  • H2C=CH-C≡CH

  • HC≡C-CH2-C≡CH


A.

H3C-C≡C-CH3

In Wacker process, alkene is oxidised into aldehyde.

CH2=CH + 12O2 H2OPdCl2/ CuCl2 CH3CHO(B)

Since, on ozonolysis, only alkenes produce aldehydes, 'A' must be an alkene. To decide the structure of alkene that undergoes ozonolysis, bring the products together in such a way that O atoms are face to face and, replace O by double (=) bond. Thus,

Therefore, alkyne must be


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93.

Which of the following is a correct statement?

  • Aqueous solutions of Cu+ and Zn2+ are colourless

  • Aqueous solutions of Cu2+ and Zn2+ are colourless

  • Aqueous solution of Fe3+ is green in colour

  • Aqueous solution of MnO-4 is colourless


94.

The percentage of lanthanides and iron respectively in misch metal are

  • 50, 50

  • 75, 25

  • 90, 10

  • 95, 5


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95.

KO2 exhibits paramagnetic behaviour. This is due to the paramagnetic nature of

  • KO-

  • K+

  • O2

  • O-2


96.

Which one of the following ions has same number of unpaired electrons as those present in V+ ion?

  • Fe3+

  • Ni2+

  • Mn2+

  • Cr3+


97.

Which of the following characteristics of the transition metals is associated with their catalytic activity?

  • Colour of hydrated ions

  • Diamagnetic behaviour

  • Paramagnetic behaviour

  • Variable oxidation states


98.

What are X and Y in the following reactions?

MnO4- + I- H+ XMnO4- + I- H2O Y

  • I2, IO4-

  • I2, IO3-

  • IO3-, IO3-

  •  IO3-,I2,


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99.

Which of the following transition metals shows the highest oxidation state?

  • Sc

  • Ti

  • Mn

  • Zn


100.

Which of the ions having following electronic structure would have maximum magnetic moment?

  • 1s2, 2s2, 2p6,3s2,3p6,3d3

  • 1s2, 2s2, 2p6,3s2,3p6,3d5

  • 1s2, 2s2, 2p6,3s2,3p6,3d7

  • 1s2, 2s2, 2p6,3s2,3p6,3d9


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