Chapter-wise MCQ Questions

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Question-1. The number of atoms present in 0.5 moles of Nitrogen atoms is same as in

  1. 12 g of C
  2. 24 g of Mg
  3. 8 g of O
  4. 32 g of S
Answer-1

Question-2. The number of molecules in 16.0g of oxygen is

  1. 6.02 × 10<sup>23</sup>
  2. 6.02 ×10<sup>-23</sup>
  3. 3.01 × 10<sup>-23</sup>
  4. 3.01 × 10<sup>23</sup>
Answer-2

Question-3. The number of oxygen atoms in 4.4 g of CO2 is approx.

  1. 6 × 1022
  2. 6
  3. 12 × 10<sup>23</sup>
  4. 1.2 × 10<sup>23</sup>
Answer-3

Question-4. The percentage of copper and oxygen in samples of CuO obtained by different methods were found to be the same. The illustrate the law of

  1. Constant proportion
  2. Conservation of mass
  3. Multiple proportions
  4. Reciprocal proportions
Answer-4

Question-5. The word ?mole? was introduced around 1896 by:

  1. Wilhelm Ostwald
  2. John Dalton
  3. Avogadro
  4. Vergilious
Answer-5

Question-6. What is the formula mass unit of ZnO?

  1. 18 u
  2. 81 u
  3. 88 u
  4. 188 u
Answer-6

Question-7. What is the latin name of sodium?

  1. Kalium
  2. Plumbum
  3. Natrium
  4. None of the above
Answer-7

Question-8. When an atom loses electrons, it is called a (an) ______ and has a _____ charge

  1. Anion, positive
  2. Cation, positive
  3. Anion, negative
  4. Cation, negative
Answer-8

Question-9. Which is not represented by 1mole of Nitrogen gas?

  1. 6.023X10<sup>23</sup> molecules of N2
  2. 12.046 X10<sup>23</sup> atoms of N2
  3. 6.023X10<sup>23</sup> atoms of N2
  4. 28g of N2
Answer-9

Question-10. Which of the following contains maximum number of molecules?

  1. 19 CO2
  2. 1 g N2
  3. 1 g H2
  4. 1 g CH4
Answer-10

Question-11. Which of the following has the smallest number of molecules?

  1. 0.1 moles of CO2
  2. 2g of H2 at STP
  3. 16g of O2 gas
  4. 3.4g of NH3
Answer-11

Question-12. Which of the following is a correct statement

  1. Na2S is sodium sulphide, Na2SO3 is sodium sulphite, Na2SO4 is sodium sulphate
  2. Na2S is sodium sulphite, Na2SO3 is sodium sulphide, Na2SO4 is sodium sulphate
  3. Na2S is sodium sulphide, Na2SO3 is sodium sulphate, Na2SO4 is sodium sulphite
  4. Na2S is sodium sulphite, Na2SO3 is sodium sulphite, Na2SO4 is sodium sulphide
Answer-12

Question-13. Which of the following is not a postulate of Daltons atomic theory

  1. All matter is made up of atoms
  2. Atoms are tiny indivisible and indestructive ultimate particles
  3. Atoms combine in small whole number ratios to form compounds
  4. Atoms of different elements can have the same mass
Answer-13

Question-14. Which of the following represents 12 u?

  1. Mass of 1 hydrogen atom
  2. Mass of C-12 atom
  3. Mass of 0-16 atom
  4. 1/12th of mass of C-12 atom
Answer-14

Question-15. Which of the following represents a correct chemical formula?

  1. CaCl
  2. BiPO4
  3. NaSO4
  4. NaS
Answer-15

Question-16. Which of the following represents the correct relation between Avogadro?s number (No), number of particles (N) and moles (n)?

  1. n = N / No
  2. n = No / N
  3. n = N No
  4. all are correct
Answer-16

Question-17. Which of the following statements is not true about an atom?

  1. Atoms are not able to exist independently
  2. Atoms are the basic units from which molecules and ions are forme
  3. Atoms are always neutral in nature.
  4. Atoms aggregate in large numbers to form the matter that we can see, feel or touch.
Answer-17

Question-18. Which one of the following phrases would be incorrect to use?

  1. A mole of an element
  2. A mole of a compound
  3. An atom of an element
  4. An atom of a compound
Answer-18

Question-19. Who coined the term ?Parmanu? for the smallest indivisible particles?

  1. Leucippus
  2. L. Lavoisier
  3. Kanad
  4. None of them
Answer-19

Question-20. Who laid the foundation of laws of Chemical Combination:

  1. Democritus
  2. Lavoisier
  3. Dalton
  4. Proust
Answer-20

Question-21. 4g of iodine and 14.2g of chlorine are made to react completely to yield a mixture of ICl and ICl3 . Calculate the ratio of moles of ICl and ICl3

  1. 1: 1
  2. 2: 1
  3. 3: 1
  4. 1: 2
Answer-21

Question-22. 18g of water is electrolyse The weight of oxygen obtained is:

  1. 8g
  2. 16g
  3. 4g
  4. 1g
Answer-22

Question-23. Atomic radius is measured in?

  1. Kg
  2. cm
  3. Mm
  4. nm
Answer-23

Question-24. Choose the law of conservation of mass

  1. Mass neither be created nor formed
  2. Mass can neither be created nor reform
  3. Mass can neither be created nor destroyed
  4. Mass can neither be created nor alive
Answer-24

Question-25. Formula for Aluminium Oxide is:

  1. AlO
  2. AlO2
  3. Al3O2
  4. Al2O3
Answer-25

Question-26. How many times an atom of sulphur is heavier than an atom of carbon?

  1. 32 times
  2. 12 times
  3. 8/3 times
  4. 12/32 times
Answer-26

Question-27. Identify the correct symbol of gold

  1. Go
  2. Ge
  3. Gd
  4. Au
Answer-27

Question-28. Molecular weight of CuSO4.5H2O is equal to

  1. 249.5
  2. 159.5
  3. 159.5 X90
  4. 159.5 +10 + 16
Answer-28

Question-29. One gram of which of the following contains largest number of oxygen atoms?

  1. O
  2. O2
  3. O3
  4. All contains same
Answer-29

Question-30. Out of 1 g of oxygen gas, 1 g of oxygen atoms and 1g of ozone , maximum number of atoms are present in

  1. 1g of oxygen gas
  2. 1g of oxygen atoms
  3. 1 g of ozone
  4. All have equal number of atoms
Answer-30

Question-31. Percentage of calcium in calcium carbonate is

  1. 40
  2. 30
  3. 48
  4. 36
Answer-31

Question-32. The atomic mass of carbon is:

  1. 12
  2. 14
  3. 16
  4. 23
Answer-32

Question-33. The balancing of chemical equations is in accordance with

  1. Law of combining volumes
  2. Law of constant proportions
  3. Law of conservation of mass
  4. Both b and c
Answer-33

Question-34. The chemical symbol for barium is

  1. B
  2. Ba
  3. Be
  4. Bi
Answer-34

Question-35. The chemical symbol for nitrogen gas is

  1. Ni
  2. N2
  3. N+
  4. N
Answer-35

Question-36. The chemical symbol for sodium is

  1. So
  2. Sd
  3. NA
  4. Na
Answer-36

Question-37. The combining capacity of an element is called

  1. Valency
  2. Atomicity
  3. Atomic number
  4. Valence electrons
Answer-37

Question-38. The correct symbol for silver is:

  1. Ag
  2. S
  3. Ar
  4. AI
Answer-38

Question-39. The formula of Calcium phosphate is

  1. CaPO4
  2. Ca(PO4)2
  3. Ca3(PO4)2
  4. Ca2(PO4)3
Answer-39

Question-40. The law of definite proportions was given by

  1. John Dalton
  2. Humphry davy
  3. Proust
  4. Michael Faraday
Answer-40

Question-41. The mass of a single atom of an element X is 2.65X 10-23g. The atomic mass and name of the element is

  1. 16u, oxygen
  2. 16u, Sulphur
  3. 32u, oxygen
  4. 32u, Sulphur
Answer-41

Question-42. The molecular formula of potassium nitrate is ________

  1. KNO3
  2. KNO
  3. KNO2
  4. KON
Answer-42

Question-43. The molecule having an atomicity of 4 is

  1. Sulphate molecule
  2. Ozone molecule
  3. Phosphorus molecule
  4. Methane molecule
Answer-43

Question-44. The most remarkable concept that Dalton?s atomic theory proposed was that of the:

  1. atomic weight
  2. atomic mass
  3. molar mass
  4. none of the above
Answer-44

Question-45. The number of atom in 4.25g of NH3 is approximately

  1. 1×10<sup>23</sup>
  2. 2×10<sup>23</sup>
  3. 4×10<sup>23</sup>
  4. 6×10<sup>23</sup>
Answer-45

Question-46. 1 amu means

  1. 1/12th mass of C-12 atoms
  2. Mass of C-12 atom
  3. Mass of O-16 atom
  4. Mass of Hydrogen molecule
Answer-46



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