You are currently viewing NEET (UG) – 2012Pre Chemistry Previous Year

NEET (UG) – 2012Pre Chemistry Previous Year

1. CH3CHO and C6H5CH2CHO can be distinguished chemically by

(1) Fehling solution test             (2) Benedict test

(3) Iodoform test                       (4) Tollen’s reagent test

2. pA and pB are the vapour pressure of pure liquid components. A and B, respectively of an ideal binary solution. If xA represents the mole fraction of component A, the total pressure of the solution will be

(1) pB + xA (pA – pB)                            (2) pA + xA (pB – pA)

(3) pA + xA (pA – pB)                           (4) pB + xA (pB – pA)

3. Which one of the following is not a condensation polymer?

(1) Neoprene                   (2) Melamine

(3) Glyptal                       (4) Dacron

4. A metal crystallizes with a face-centered cubic lattice. The edge of the unit cell is 408 pm. The diameter of the metal atom is :

(1) 204 pm            (2) 288 pm

(3) 408 pm            (4) 144 pm

5. Equimolar solutions of the following substances were prepared separately. Which one of these will record the highest pH value?

(1) BeCl2               (2) BaCl2

(3) AlCl3                (4) LiCl

6.

(a)

(b)

(c)

(d)

7. The enthalpy of fusion of water is 1.435 kcal/mol. The molar entropy change for the melting of ice at 0°C

(1) 0.526 cal/(mol K)      (2) 10.52 cal / (mol K)

(3) 21.04 cal / (mol K)    (4) 5.260 cal/(mol K)

8. Limiting molar conductivity of NH4OH (i.e. m ˄m (NH4OH) ) is equal to:

(1) ˄m (NH4Cl) + ˄m (NaOH) – ˄m (NaCl)

(2) ˄m (NH4Cl) + ˄m (NaCl) – ˄m (NaOH)

(3) ˄m (NaOH) + ˄m (NaCl) – ˄m (NH4Cl)

(4) ˄m (NH4OH) + ˄m (NH4Cl) – ˄m (HCl)

9. Which one of the following is a mineral of iron?

(1) Magnetite                   (2) Malachite

(3) Cassiterite                   (4) Pyrolusite

10. In Freundlich Adsorption isotherm, the value of 1/n is:

(1) 1 in case of chemisorption (2) between 0 and 1 in all cases

(3) between 2 and 4 in all cases (4) 1 in case of physical adsorption

11. Identify the alloy containing a non-metal as a constituent in it.

(1) Bronze             (2) Invar

(3) Steel                 (4) Bell metal

12. Buffer solutions have constant acidity and alkalinity because:

(1) they have fixed value of pH

(2) these give unionised acid or base on reaction with added acid or alkali

(3) acids and alkalies in these solutions are shielded from attack by other ions

(4) they have large excess of H+ or OH ions

13. Which one of the following pairs is isostructural (i.e. having the same shape and hybridization)?

(1) [BF4and NH4+ ]                  (2) [BCl3 and BaCl3 ]

(3) [NH3 and NO3 ]                  (4) [NF3 and BF3]

14. pH of a saturated solution of Ba(OH)2 is 12. The value of solubility product (Ksp) of Ba(OH)2 is

(1) 5.0 × 10–6                   (2) 3.3 × 10–7

(3) 5.0 × 10–7                   (4) 4.0 × 10–6

15. 50 mL of each gas A and of gas B takes 150 and 200 seconds respectively for effusing through a pin hole under the similar conditions. If molecular mass of gas B is 36, the molecular mass of gas A will be

(1) 64                    (2) 96

(3) 128                  (4) 32

16. The protecting power of lyophilic colloidal sol is expressed in terms of

(1) Oxidation number                (2) Coagulation value

(3) Gold number                        (4) Critical miscelle concentration

17. Deficiency of vitamin B1 causes the disease

(1) Sterility            (2) Convulsions

(3) Beri-Beri          (4) Cheilosis

18. Acetone is treated with excess of ethanol in the presence of hydrochloric acid. The product obtained is:

(a)