11th class (FSc) chemistry Unit 1 MCQs
26. The number of isotopes of cadmum (Cd) is:
a. Five
b. Six
c. Nine
d. Seven
27. Bromine has isotopes:
a. 4
b. 8
c. 2
d. 6
28. Nickel has isotopes:
a. 6
b. 3
c. 11
d. 5
29. Number of isotopes of arsenic:
a. 3
b. 1
c. 9
d. 2
30. Dempster’s mass spectrometer was designed for the identification ofisotopes of the elements which were availabe in:
a. Solid state
b. Gaseous state
c. Plasma state
d. Liquid state
32. The pressure of vapours maintained in ionization chamber of massspectrometer during isotopic analysis is:
a. Around 10-7 torr
b. 103 torr
c. 10-9 torr
d. Around 10-5 torr
33. One of the substance is used to absorb CO2 gas in combustionanalysis, which is that substance:
a. Mg(ClO4)2
b. 50 % KOH
c. SiO2
d. Al2O3
34. In combustion analysis water vapors are absorbed in:
a. NaOH
b. 50% KOH
c. MgCl2
d. Mg(ClO4)2
35. Emperical formula of glucose is:
a. CH2O
b. CHO
c. C6H12O6
d. C2H4O2
36. Ascorbic acid is vitamin:
a. C
b. A
c. D
d. B
37. During combustion analysis Mg(CIO4) is employed to absorb:
a. CH4
b. CO2
c. CO
d. H2O
38. The largest number of molecules are present:
a. 2.8 g of CO
b. 3.6 g of H2O
c. 5.4 g of N2O5
d. 4.8 g of C2H5OH
39. The mass of one mole of electron is:
a. 0.184mg
b. 1.0088
c. 1.673mg
d. 0.55mg
40. The mass of CO2 containing 8 grams of oxygen in gram is:
a. 16
b. 32
c. 11
d. 22
41. The number of moles of CO2 which contain 8.0 g of oxygen:
a. 1.0
b. 0.25
c. 1.5
d. 0.50
42. The number of moles of hydrogen atoms in 92g alcohol (C2H5OH)are:
a. 10 moles
b. 5 moles
c. 12 moles
d. 6 moles
43. The number of moles in one gram molecule of CO2 is:
a. 6.27 x 1027
b. 6.02 x 1023
c. 6.02 x 1024
d. 6.02 x 1022
44. The number of carbon atoms in 22.0 g of CO2 is:
a. 3.01 x 1022
b. 3.01 x 1023
c. 6.02 x 1022
d. 6.02 x 1023
45. Formula mass of CaCO3 is:
a. 120
b. 100
c. 106
d. 90
46. The number of atoms present in 0.5 mole of Na is:
a. 2.04 x 1023
b. 1.0 x 1023
c. 3.01 x 1023
d. 6.02 x 1023
47. Number of molecule in one dm3 of H2O is close to:
a. 18 x 6.022 x1023
b. 6.022 x 1023
c. 55.5 x 6.022 x1023
d. None of these
48. A ring has 6.0 g of diamond (C) in it. Calculate the number of atoms of carbon in it:
a. 9.03 x 1023
b. 6.02 x 1023
c. 1.8 x 1024
d. 3.01 x 1023
49. The volume occupied by 28g of N2 at STP is:
a. 224.14 dm3
b. 22.414 dm3
c. 1.12 dm3
d. 2.2414 dm3
50. The volume occupied by 4.4g of CO2 at S.T.P is:
a. 112 cm3
b. 2.24 dm3
c. 1.12 dm3
d. 22.4 dm3