Chemistry Chapter 1 Entry Test MCQs
51. Which among the following is the lowest mass?
a. 22.414dm3 of O2 at STP
b. One mole of nitrogen
c. 20g of Neon
d. 6.02×1023 molecules of CO2
52. Which of the following sample contains the largest number of atoms?
a. 1 g of N2
b. 1 g of Ni
c. 1 g of B
d. 1 g of Ca
53. The weight of 11.2 dm3 of CO2 at STP would be
a. 32 g
b. 88 g
c. 22 g
d. 44 g
54. Which one of the following is correct formula to find number of molecules?
a. n × NA× atomicity
b. m × M
c. n × NA
d. mass / molar mass
55. Least number of molecules of oxygen are present in
a. 1.5 moles of hydrogen peroxide
b. 2 moles of carbon dioxide
c. 4 moles of water
d. 3 moles of sulphur dioxide
56. Molecular formula = n (Empirical formula), here the value of n cannot be
a. +3, +1
b. +1, +4
c. +1, +2
d. 0, -1
57. Which of these will have the lowest number of hydrogen atoms, if equal number of moles of all of these are present
a. NH3
b. HF
c. CH4
d. H2O
58. What is true about molar volume at STP?
a. It is the volume of 1 mole of real gas
b. It is the volume of 1 mole gas
c. It is the volume of one mole of ideal liquid
d. It is the volume of one mole ideal gas
59. When comparing the volumes of equal masses of different ideal gases, smaller the molar mass of a gas, ________will be its occupied volume at STP?
a. zero
b. Higher
c. negligible
d. Lower
60. Which of the following does not represent a mole?
a. atomic mass expressed in grams
b. formula mass expressed in grams
c. molecular mass expressed in grams
d. molar volume expressed in grams
61. 4g silicon (atomic mass=28amu) contain atoms
a. 6.02 x 1024
b. 6.02 x 1022
c. 3.01 x 1023
d. 6.02 x 1023
62. 3.2g of CH3OH & 1.6g of CH4 have
a. equal no. of molecules
b. different no. of molecules
c. 4 moles of hydrogen
d. same mass of carbon
63. Which of the following contains maximum number of hydrogen atoms?
a. 0.25 moles of glucose
b. 1 mole of water
c. 0.25 moles of sucrose
d. 0.5 moles of methane
64. 1 mole of an ideal gas occupies a volume of 22.414dm3 at STP. If 22.414dm3 of different ideal gases are present which of the following quantity is always the same for all of them
a. Number of molecules
b. number of atoms
c. Number of protons in nucleus
d. Number of electrons
65. 0.25 moles of all the ideal gases occupy a volume of_________dm3 at STP
a. 1.12
b. 0.56
c. 11.2
d. 5.6
66. Volume occupied by 1 mole of a substance is 22.4dm3 at STP, the substance cannot be
a. water
b. Helium
c. Argon
d. Hydrogen
67. Which formula does not give moles of a substance
a. given volume/ molar volume
b. mass/ molar mass
c. mass × molar mass
d. No. of particles/ NA
68. Moles of NaHCO3 containing 11.5g Na are
a. 0.5
b. 1
c. 0.25
d. 2
69. The total number of protons in 10 g of calcium carbonate is (NA=6.023×1023)
a. 30.1×1024
b. 3.01×1024
c. 3.01×1023
d. 4.06×1024
70. Eight grams of methane occupies volume at STP
a. 1.12 dm3
b. 22.4 dm3
c. 11.2 dm3
d. 2.24 dm3
71. 15 gram of a gas occupies 11.2 dm3 at S.T.P, the gas is
a. CO2
b. CO
c. N2O
d. NO
72. Which one is incorrect relation at STP?
a. 11.2 dm3 of CO2 = 3.01´1023 molecules
b. 6g of carbon = 3.01´1023 atoms
c. 1 mole of sucrose = 45 moles of atoms
d. 49 g of H2SO4 = 4 moles of atoms
73. If a piece of copper weighs 0.635g how many atoms does it contain (Cu = 63.5 amu)
a. 6.023 × 1023
b. 6.023 × 1021
c. 6.02 × 1024
d. 6.02 × 1022
74. Avogadro’s number is the number of molecules present in
a. 1000 cm3 at STP
b. 11.2 dm3 at STP
c. 1 cm3 at STP
d. 22400 cm3 at STP
75. What volume is occupied by a mixture of 0.5g H2, 16g O2 and 7.0g N2
a. 0.224 dm3
b. 2.24 dm3
c. 11.2 dm3
d. 22.4 dm3