Class 10 Science

Periodic Classification of Elements

NCERT Exemplar Problems

MCQ Part 1

Question 1: Upto which element, the Law of Octaves was found to be applicable

  1. Oxygen
  2. Calcium
  3. Cobalt
  4. Potassium
    Answer: (b) Calcium

Question 2: According to Mendeleev's Periodic Law, the elements were arranged in the periodic table in the order of

  1. Increasing atomic number
  2. Decreasing atomic number
  3. Increasing atomic masses
  4. Decreasing atomic masses
    Answer: (c) Increasing atomic masses

Question 3: In Mendeleev’s Periodic Table, gaps were left for the elements to be discovered later. Which of the following elements found a place in the periodic table later

  1. Germanium
  2. Chlorine
  3. Oxygen
  4. Silicon
    Answer: (a) Germanium

Question 4: Which of the following statement (s) about the Modern Periodic Table are incorrect

  1. The elements in the Modern Periodic Table are arranged on the basis of their decreasing atomic number
  2. The elements in the Modern Periodic Table are arranged on the basis of their increasing atomic masses
  3. Isotopes are placed in adjoining group (s) in the Periodic Table
  4. The elements in the Modern Periodic Table are arranged on the basis of their increasing atomic number
  1. (i) only
  2. (i), (ii) and (iii)
  3. (i), (ii) and (iv)
  4. (iv) only
    Answer: (b) (i), (ii) and (iii)

Question 5: Which of the given elements A, B, C, D and E with atomic number 2, 3, 7, 10 and 30 respectively belong to the same period?

  1. A, B, C
  2. B, C, D
  3. A, D, E
  4. B, D, E
    Answer: (b) B, C, D

Question 6: The elements A, B, C, D and E have atomic number 9, 11, 17, 12 and 13 respectively. Which pair of elements belongs to the same group?

  1. A and B
  2. B and D
  3. A and C
  4. D and E
    Answer: (a) A and B

Question 7: Where would you locate the element with electronic configuration 2,8 in the Modern Periodic Table?

  1. Group 8
  2. Group 2
  3. Group 18
  4. Group 10
    Answer: (c) Group 18

Question 8: An element which is an essential constituent of all organic compounds belongs to

  1. Group 1
  2. Group 14
  3. Group 15
  4. Group 16
    Answer: (b) Group 14

Question 9: Which of the following statements about the Modern Periodic Table is correct:

  1. It has 18 horizontal rows known as Periods
  2. It has 7 vertical columns known as Periods
  3. It has 18 vertical columns known as Groups
  4. It has 7 horizontal rows known as Groups
    Answer: (c) It has 18 vertical columns known as Groups