31.

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

• KO^-

• K⁺

• O₂

• O^-₂

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

• Fe³⁺

• Ni²⁺

• Mn²⁺

• Cr³⁺

Match the following

Column I	Column II
(A) sp3	(i) [Co(NH3)6]3+
(B) dsp2	(ii) [Ni(CO)4]
(C) sp3d2	(iii) [Pt(NH3)2Cl2]
(D) d2sp3	(iv) [CoF6]3-
	(v) [Fe(CO)5]

• A    B    C    D

  (v) (ii)  (i)  (iii)

• A    B    C    D

  (ii)  (iii) (iv) (v)

• A    B    C    D

  (ii) (iii) (i)  (v)

• A    B     C     D

  (iii) (ii)  (iv)  (i)

What is Z in the following reaction sequence?

• C₆H₅CO₂H

• C₆H₅OH

• C₆H₅CHO

• C₆H₆

${\mathrm{CH}}_3\mathrm{MgBr} + {\mathrm{CO}}_2 \stackrel{\mathrm{Dry}\hspace{0.17em}\mathrm{ether}}{\to } \mathrm{Y} \stackrel{{\mathrm{H}}_3{\mathrm{O}}^{\oplus }}{\to } \mathrm{Z}$ . Identify Z from the following.

• Ethyl acetate

• Acetic acid

• Propanoic acid

• Methyl acetate.

$\mathrm{X} \stackrel{\mathrm{Y}}{\to } \mathrm{Benzoquinone}$. Identify X and Y inthe above reaction.

• X	Y
  	Zn

• X	Y
  	Na2Cr2O7/ H2SO4

• X	Y
  	Na2Cr2O7/ H2SO4

• X	Y
  	Zn

${\mathrm{C}}_6{\mathrm{H}}_5- \mathrm{O}- {\mathrm{CH}}_2- {\mathrm{CH}}_3\stackrel{∆, \mathrm{HI}}{\to } \mathrm{Y}+ \mathrm{Z}$

Identify Y and Z inthe above reaction.

•  

  X	Y
  C6H5OH	H3CCH3

•  

  X	Y
  C2H5I	C6H5CHO

• X	Y
  C6H5I	H3CCH2OH

• X	Y
  C6H5OH	H3CCH2I

What are the substances which mimic the natural chemical messengers?

• Antibiotics

• Antagonists

• Agonists

• Receptors

Lactose is disaccharide of

• α- D - glucose and α- D - fructose

• β- D- glucose and β- D-galatose

• α- D - glucose and  β- D-ribose

• α- D - glucose and  β- D-galactose

Identify the copolymer from the following