A fresh set of 20 random questions is generated every time you open this page and every time you refresh it.For each of the following multiple choice questions, choose the most appropriate answer :
1. The geometry of electron pairs around I in IF5 is
A. Trigonal bipyramidal
B. Octahedral
C. Square pyramidal
D. Pentagonal planar
2. During fermentation of sugar, the chief compound always formed is
A. methyl alcohol
B. ethyl alcohol
C. acetic acid
D. ethylene
3. Carbon can reduce ferric oxide to iron at a temperature above 983 K because
A. iron has a higher affinity towards oxygen than carbon.
B. carbon monoxide formed is thermodynamically less stable than ferric oxide.
C. carbon has a higher affinity towards oxidation than iron.
D. free energy change for the formation of carbon dioxide is less negative than that for ferric oxide.
4. The method that cannot be used for removing permanent hardness of water is
A. adding sodium carbonate
B. distillation
C. adding caustic soda
D. boiling
5. The pH of human blood is around
A. 3
B. 7.5
C. 12
D. 6
6. Washing soda is
A. sodium chloride
B. hydrated sodium carbonate
C. sodium bicarbonate
D. calcium carbonate
7. Clemmensen reduction of a ketone is carried out in the presence of which of the following?
A. H2 and Pt as catalyst
B. LiAlH4
C. Glycol with KOH
D. Zn-Hg with HCl
8. The number of disulphide linkages present in insulin are
A. 1
B. 2
C. 4
D. 3
9. Turpentine oil is obtained from the wood of
A. Gnetum
B. Mycas
C. Cedrus
D. Pinus
10. Producer gas chemically consists of
A. CO+H2
B. CO+N2
C. CO2+N2
D. CO2+H2
11. The compound which gives turbidity immediately with Lucas reagent at room temperature is
A. butan-1-ol
B. 2-methyl propan-1-ol
C. butan-2-ol
D. 2-methyl propan-2-ol
12. M. Therefore the number of unpaired electrons present in it is
A. 4
B. 2
C. 3
D. 1
13. Which of the following species does not exert a resonance effect?
A. C6H5NH2
B. C6H5NH3
C. C6H5Cl
D. C6H5OH
14. The maximum concentration of alcohol that does not impair faculties of the human body is
A. 23 mg/100ml
B. 9 mg/100 ml
C. 3 mg/100 ml
D. 1mg/100 ml
15. Serpasil is
A. tranquilizer
B. not natural product
C. produced by micro-organisms
D. a mordant dye
16. Silver halides are used in photographic plates because they are
A. oxidised in air
B. colourless
C. easily soluble in hypo solution
D. readily reduced by light
17. Synthetic detergents are
A. sodium salts of fatty acids
B. a mixture of sodium carbonate and sodium chloride
C. calcium salts of hydrochloric acid
D. a mixture of sodium salts of aromatic and aliphatic sulphonic acids
18. Hypo, used in photography, is chemically
A. silver bromide
B. sodium thiosulphate
C. sodium phosphate
D. silver nitrate
19. If the enthalpy change for the transition of liquid water to steam is 30 kJ mol–1 at 27°C, the entropy change for the process would be
A. 0.1 J mol–1 K–1
B. 100 J mol–1 K–1
C. 1.0 J mol–1 K–1
D. 10 J mol–1 K–1
20. In acetylene molecule, between the carbon atoms there are
A. three pi bonds
B. three sigma bonds
C. one sigma and two pi bonds
D. two sigma and one pi bonds
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