Chemistry Mcqs (Sample type)
 

1. When KBr is dissolved in water, K+ ions are

(A) oxidised

(B) reduced

(C) hydrolysed

[B](D) hydrated[/B]

2. When sulphur dioxide is passed in an acidified K2Cr2 O7 solution, the oxidation state of sulphur is changed from

(A) + 4 to 0

(B) + 4 to + 2

[B](C) + 4 to + 6[/B]

(D) + 6 to + 4

3. When the azimuthal quantum number has the value of 2, the number of orbitals possible are

(A) 7

[B](B) 5[/B]

(C) 3

(D) O

4. Which complex can not ionise in solution?

(A) [Pt(NH3)6] Cl4

(B) K2[pt(F6)]

(C) K4[Fe(CN)6]

[B](D) [CoCl3(NH3)3][/B]

5. Which is the most easily liquifiable rare gas?

[B](A) Xe[/B]

(B) Kr

(C) Ar

(D) Ne

6. Which metal has a greater tendency to form metal oxide?

(A) Cr

(B) Fe

(C) Al

[B](D) Ca[/B]

7. Which of the following can be measured by the Ostwald-Walker dynamic method

[B](A) Relative lowering of vapour pressure[/B]

(B) Lowering of vapour pressure

(C) Vapour pressure of the solvent

(D) all of these

8. Which of the following compounds has the lowest melting point?

(A) CaF2

(B) CaCl2

(C) CaBr2

[B](D) CaI2[/B]

9. Which of the following electrolytic solutions has the least specific conductance `?

(A) 0.02 N

(B) 0.2 N

(C) 2 N

[B](D) 0.002 N[/B]

10. Which of the following elements is present as the impurity to the maximum extent in the pig iron?

(A) Phosphorus

(B) Manganese

[B](C) Carbon[/B]

(D) Silicon

11. The enthalpy of vaporization of benzene is +35.3 kJ/mol at its boiling point of
80°C. The entropy change in the transition of vapour to liquid at its boiling point is ______.

[in J mol–1 K–1]

(A) +100

[B](B) –100[/B]

(C) –342

(D) +342

12. The formation of [PtF6]- is the basis for the formation of Xenon fluorides. This is because

(A) O2 and Xe have comparable sizes

(B) both O2 and Xe are gases

[B](C) O2 and Xe have comparable ionisation energies[/B]

(D) O2 and Xe have comparable electronegativities

13. The formula mass of Mohr's salt is 392. The iron present in it is oxidised by KMnO4 in acid

medium. The equivalent mass of Mohr's salt is

[B](A) 392[/B]

(B) 31.6

(C) 278

(D) 156

14. The geometry of electron pairs around I in IF5 is

[B](A) Octahedral[/B]

(B) Trigonal bipyramidal

(C) Square pyramidal

(D) Pentagonal planar

15. The half life time of 2g sample of radioactive nuclide 'X' is 15 min. The half life time of 1g sample of X is

(A) 7.5 min

[B](B) 15 min[/B]

(C) 22.5 min

(D) 30 min

16.

The highest magnetic moment is shown by the transition metal ion with the configuration

(A) 3d2

[B](B) 3d5[/B]

(C) 3d7

(D) 3d9

17. The IUPAC name of the complex [Co (NH3)4Cl2] Cl is

[B](A) tetraammine dichloro cobalt (III) chloride[/B]

(B) dichloro tetraammine cobalt (III) chloride

(C) tetraammine dichloro cobalt (IV) chloride

(D) tetraammine dichloro cobalt (II) chloride

18. The mass of glucose that should be dissolved in 50 g of water in order to produce the same lowering of vapour pressure as is produced by dissolving 1 g of urea in the same quantity of water is

(A) 1 g

[B](B) 3 g[/B]

(C) 6 g

(D) 18 g

19. The maximum number of possible isomers in 1-bromo-2-methyl cyclobutane is

(A) 2

[B](B) 4[/B]

(C) 16

(D) 8

20. The pH of 10-8 M HCI solution is

(A) 8

(B) more than 8

[B](C) between 6 and 7[/B]

(D) slightly more than 7

21. In Ramsay and Rayleigh's isolation of noble gases from air, the nitrogen of the air is finally converted into

(A) NO and NO2

(B) NaNO2 only

[B](C) NaNO2 and NaNO3[/B]

(D) NaNO3 only

22. In chromite ore, the oxidation number iron and chromium are respectively ______.

(A) +3, +6

(B) +3, +2

[B](C) +2, +3[/B]

(D) +2, +6

23. In aqueous solution glucose remains as

(A) Only in open chain form

(B) Only in pyranoze form

(C) Only in furanose forms

[B](D) In all three forms in equilibrium[/B]

24. In an alkaline medium, glycine predominantly exists as/in a /an

[B](A) anion[/B]

(B) cation

(C) covalent form

(D) zwitterions

25. If the molecular wt. of Na2S2O3 and I2 are M1 and M2 respectively, then what will be the equivalent wt. of Na2S2O3 and I2 in the following reaction?

2S2 + I2 ¾® S4 + 2I-

(A) M1, M2

[B](B) M1, M2/2[/B]

(C) 2M1, M2

(D) M1,2M2

26. If the energies of the two photons are in the ratio of 3: 2, their wavelengths will be in the ratio of

[B](A) 2: 3[/B]

(B) 9: 4

(C) 3: 2

(D) 1: 2

27. Identify B and D is the following sequence of reactions.

(A) Ethyl hydrogen sulphate and alcoholic KOH

(B) Methanol and bromoethane

[B](C) Ethanol and alcoholic KOH[/B]

(D) Ethyl hydrogen sulphate and aqueous KOH

28. Hydrogen is prepared from H2O by adding

[B](A) Ca, which acts as reducing agent[/B]

(B) AI, which acts as oxidising agent

(C) Ag, which acts as reducing agent

(D) Au, which acts as oxidising agent

29. Hydrogen bond is strongest in

(A) S — H —— O

(B) O — H —— S

[B](C) F — H —— F[/B]

(D) O — H —— N

30. Hybridization of C2 and C3 of H3C – CH = C = CH – CH3 are

(A) Sp, Sp3

[B](B) Sp2, Sp[/B]

(C) Sp2, Sp2

(D) Sp, Sp