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QUESTION BASED ON IMPORTANT TOPICS OF CHEMISTRY FOR AIPMT

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1. If pH of a saturated solution of Ba 2(OH) is 12, the value of 

its (sp)K  is :

(a) 4.00 × 6 310 M (b) 4.00 × 10 –7 M3

(c) 5.00 ×6 3

10 M

(d) 5.00 × 7 310 M

2. In qualitative analysis, the metals of Group I can be separated 

from other ions by precipitating them as chloride salts. A

solution initially contains Ag+ and Pb2+ at a concentration

of 0.10 M. Aqueous HCl is added to this solution until the

Cl –  concentration is 0.10 M. What will the concentrations of 

Ag+ and Pb2+ be at equilibrium?

(K sp for AgCl = 1.8 × 10 –10,

K sp for PbCl2 = 1.7 × 10 –5)

(a) [Ag+] = 1.8 × 10 –7 M ; [Pb2+] = 1.7 × 10 –6 M

(b) [Ag+] = 1.8 × 10 –11 M ; [Pb2+] = 8.5 × 10 –5 M

(c) [Ag+] = 1.8 × 10 –9 M ; [Pb2+] = 1.7 × 10 –3 M

(d) [Ag+] = 1.8 × 10 –11 M ; [Pb2+] = 8.5 × 10 –4 M3. Which one of the following molecular hydrides acts as a

Lewis acid?

(a) NH3 (b) H2O

(c) B2H6 (d) CH4

4. The val ues of K sp  of CaCO3  a nd CaC2O4  are

4.7 × 10 –9 and 1.3 × 10 –9 respectively at 25°C. If the mixture

of these two is washed with water, what is the concentration

of Ca2+ ions in water?

(a) 7.746 × 10 –5 M (b) 5.831 × 10 –5 M

(c) 6.856 × 10 –5 M (d) 3.606 × 10 –5 M

5. In the presence of platinum catalyst, hydrocarbon A adds

hydrogen to form n-hexane. When hydrogen bromide isadded to A instead of hydrogen, only a single bromo

compound is formed. Which of the following is A?

(a) 3223 CH — CH — CHCH — CH — CH  

(b) 3223 CH — CHCH — CH — CH — CH  

(c) 3223 CH — CH — CH — CHCH — CH  

(d) 32222 CH — CH — CH — CH — CHCH  

6. The compound 

3

3|

3 CH — CH

CH

C — CH  

on reaction with NaIO4 in the presence of KMnO4 gives

(a) CH3CHO + CO2(b) CH3COCH3

(c) CH3COCH3 + CH3COOH

(d) CH3COCH3 + CH3CHO

7. 3 2|

3

H C CH CH CH HBr A

CH

A(predominantly) is :

(a)3 2 2

|

3

CH CH CH CH Br  

CH

(b) 3 2 3

3

Br 

|CH C CH CH

|CH

(c) 3 3

3

CH CH CH CH| |Br CH

(d) 3 3

3

CH CH CH CH| |

CH Br  

8. Which one of the following alkenes will react faster with

H2 under cata lytic hydrogenation conditions?(R = Alkyl Substituent)

(a)R R 

HH(b)

R 

R 

H

H

(c)R R 

HR (d)

R 

R 

R 

R 

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9. Cuprous compounds such as CuCl, CuCN and CuSCN are

the only salts stable in water due to

(a) high hydration energy of Cu+ ions

(b) their inherent tendency not do disproportionate

(c) diamagnetic nature

(d) insolubility in water 

10. CrO3 dissolves in aqueous NaOH to give

(a) Cr  2O72–  (b) CrO4

2– 

(c) Cr(OH)3 (d) Cr(OH)211. The basic character of the transition metal monoxides follows

the order 

(Atomic Nos.,Ti = 22, V = 23, Cr = 24, Fe = 26)

(a) TiO > VO > CrO > FeO

(b) VO > CrO > TiO > FeO

(c) CrO > VO > FeO > TiO

(d) TiO > FeO > VO > CrO

12. Among the following series of transition metal ions, the one

where all metal ions have 3d 2 electronic configuration is(At.

nos. Ti = 22; V = 23; Cr = 24; Mn = 25)

(a)   4323 Mn,Cr ,V,Ti

(b)   764 Mn,Cr ,V,Ti

(c)   3234 Mn,Cr ,V,Ti

(d)   5432 Mn,Cr ,V,Ti

13.2

HCl

3 3 3H O3CH COCH

 

(A)

3 2 3 2(CH ) C CH CO CH C(CH )

(B)

This polymer (B) is obtained when acetone is saturated withhydrogen chloride gas, B can be

(a) phorone

(b) formose

(c) diacetone alcohol

(d) mesityl oxide.

14. The reagent (s) which can be used to distinguish

acetophenone from benzophenone is (are)

(a) 2,4- Dinitrophenylhydrazine

(b) Aqueous solution of NaHSO3

(c) Benedict reagent

(d) I2and NaOH.

15. Schotten-Baumann reaction is a reaction of phenols with

(a) Benzoyl chloride and sodium hydroxide

(b) Acetyl chloride and sodium hydroxide

(c) Salicylic acid and conc. H2SO4

(d) Acetyl chloride and conc H2SO4

16. Acetaldehyde reacts with semicarbazide and forms

semicarbazone. Its structure is

(a) CH3CH = NNHCON = CHCH3

(b) CH3CH = NNHCONH2

(c)2

|3 CONH — 

OH

 N —  NCHCH  

(d) CH3CH = N—CONHNH2

17. A solution containing 10 g per dm3 of urea (molecular mass

= 60 g mol –1) is isotonic with a 5% solution of a non-volatile

solute. The molecular mass of this nonvolatile solute is

(a) 300 g mol –1 (b) 350 g mol –1

(c) 200 g mol –1 (d) 250 g mol –1

18. The freezing point depression constant for water is – 1.86ºC

m –1. If 5.00 g Na2SO4 is dissolved in 45.0 g H2O, the freezing

 point is changed by – 3.82ºC. Calculate the van’t Hoff factorfor Na2SO4.

(a) 2.05 (b) 2.63

(c) 3.11 (d) 0.381

19. The van’t Hoff factor i for a compound which undergoes

dissociation in one solvent and association in other solvent

is respectively :

(a) less than one and greater than one.

(b) less than one and less than one.

(c) greater than one and less than one.

(d) greater than one and greater than one.20. Which one of the following salts will have the same value

of van’t Hoff factor (i) as that of K 4[Fe (CN)6].

(a) Al2(SO4)3(b) NaCl

(c) Al (NO3)3

(d) Na2SO4.