Chemistry MCQ Quiz Hub

1. Hypochlorous acid is used for disinfecting the water it reacts with the dissolved ammonia producing
NH2Cl
NHCI2
NCI2
all of the above

2. Acid present in acid rain may be
H2SO4
HNO3
both a and b
none

3. The yellow colour in photochemical smog is due to presence of
dinitrogen oxide
nitrogen dioxide
chlorine gas
chlorine dioxide

4. Which of the following is not a condition for the formation of smog?
sufficient NO
sunlight
less movement of air
winds

5. Incineration of muncipal waste is carried out in the temperature range of
250 to 500?C
500 to 900?C
950 to 1300?C
900 to 1000?C

6. In which of the following layer of atmosphere there is more thickness of ozone layer?
troposphere
stratosphere
mesosphere
photosphere

7. Which of the following is not primary pollutant
SO3
CO
NO
H2SO4

8. Which of the following air pollutants is more dangerous for ozone layer?
CFC
CO2
CO
Oxides of nitrogen

9. Which of the following gases is the main cause of acid rain?
CO
NO2
both a & b
none of the above

10. Which statement is wrong?
the amount of ozone layer is greater in the region close to the equator
ozone acts as filter for UV radiations
in the equatorial region it acts as pollutant
CFCs play effective role in removing O3 in the stratosphere

11. Which of the following factors help to measure quallity of water?
DO
BOD
COD
all of the above

12. In the purification of portable water the coagulant used is
alum
nickel sulphate
copper sulphate
barium sulphate

13. Newspaper can be recycled again and again how many times?
2
3
4
5

14. The main pollutant of leather tanneries in the waste water is
chromium III
chromium IV
chromium V
chromium VI

15. A single chlorine free radical can destroy how many ozone molecules?
10
100
10000
100000

16. Which substance can be used for disinfecting water?
KMnO4
Alums
Ozone
All

17. Chlorination of water may be harmful if the water contains
Ammonia
Dissolved oxygen
Carbon dixide
All

18. Which one of the following makes the bulk of hydrospheres content?
oceans
glaciers & icecaps
fresh water lakes and ponds
All have equal distribution

19. Which of the following is used as water disinfectant to avoid the formation of toxic compounds
Cl2
O3
ClO2
both b & c

20. The percentage of suspended solid waste in raw water is removed by coagulation is
60
70
80
90

21. Ozone hole is substantial depletion of ozone in every year during
Aug - Nov
Sep - Nov
Nov - Dec
Dec - Jan

22. The main product of bacterial action is
Nox
NO2
N2O3
NO

23. Pollutants have adverse effect over
Biosphere
Ecosystem
Both a & b
Hydrosphere

24. Diameter of an atom is in the order of
0.2m
0.2mm
0.2nm
0.2pm

25. Which of the following are isoelectronic species?
H+ H H-
Li+ Na+ K+
C1- Br- I
F- Ne Na+

26. Mass spectrometer is used to determine Mass number of isotopes and
Atomic number
Relative abundance
Electronic configuration
All of the above

27. Molecular ions are formed by passing
High energy electron beam
? - particle
X-rays
All of the above

28. The number of peaks obtained in mass spectrometry shows
Relative abundance
Average mass of element
Number of isotopes
Relative isotopic mass

29. Empirical formula of chloroform is
CH2 C12
CH3C1
CC14
CHC13

30. Which one is true about isotope?
Same number of neutrons
Same mass number
Same physical properties
Same chemical properties

31. Molecular mass of water (18g) means
1-mole molecules of water
1-gram molecule of water
3-gram atoms
all

32. Which of the following ion formation is always exothermic?
Uni-negative
Uni-positive
Di-negative
Di-positive

33. Which of the following statements about isotopes is correct?
Isotopes with odd atomic number are abundant
Isotopes with odd atomic number and even mass number are abundant
Isotopes with even atomic number and even mass number are abundant
Isotopes with even atomic number and odd mass no are abundant

34. The sample of isotopes of an element which needs not to be vaporized in the vaporization chamer
Gas
Liquid
Volatile solid
All

35. One mole of CO2 contains.
6.022 x 1023 atoms of oxygen
22-gram electrons
6.022 x 1023 atms of carbon
both b & c

36. Avogadros number may represent
volume of particles
number of particles
mass of particles
All of the above

37. The number of isotopes of elements with even mass number and even atomic number are.
280
300
154
54

38. Size of molecule depends upon
Atomicity
Shape of molecule
Both a and b
Difficult to predict

39. Which of the following terms is not used for ionic compound?
formula unit
empirical formula
molecular formula
formula mass

40. 0.36 moles of each aluminium and oxygen react with each other to produce aluminium oxide. The amount of product formed is
0.18 mole
0.27 mole
0.24 mole
0.09 mole

41. Which of the following terms is used for the mass of chlorine 35.5?
relative atomic mass
mass number
atomic weight
relative isotopic mass

42. Which one of the following has the maximum number of isotopes?
oxygen
carbon
tin
chlorine

43. Which one of the following is not the mono isotopic element?
arsenic
uranium
iodine
nickel

44. The volume occupied by 2.8 g of N2 at STP
2.24 dm3
22.4 dm3
1.12 dm3
112 dm3

45. The mass of decimole of electrons (NA) is
1.008 mg
0.184 mg
0.054 mg
5.4 mg

46. The number of moles of CO2 which contains 16 g of oxygen is
0.25
0.5
0.75
1

47. Which of the following statements is wrong about isotopes?
they possess different mass number
they possess different physical properties
they possess same chemical properties
they possess different position in the periodic table

48. How many isotopes have odd atomic number?
154
280
86
300

49. Qualitative analysis is carried out for
identification of elements
estimation of amounts of elements
molar ration of elements
molar volume of elements

50. Percentage of calcium in calcium carbonate is
80%
30%
40%
20%