MCQ Questions for Class 10 Science: Ch 5 Periodic Classification of Elements
1. The most distinctive property of the noble gases is that they are:
(a) Unreactive
(b) Radioactive
(c) Metalloid
(d) Metallic
► (a) Unreactive
(a) Unreactive
(b) Radioactive
(c) Metalloid
(d) Metallic
► (a) Unreactive
2. According to IUPAC recommondations, the number of groups in the long form of the periodic table is:
(a) 7
(b) 8
(c) 16
(d) 18
► (d) 18
3. Upto which element, the Law of Octaves was found applicable?
(a) Oxygen
(b) Calcium
(c) Cobalt
(d) Potassium
► (b) Calcium
4. At the time of Mendeleev, the number of elements known was
(a) 63
(b) 65
(c) 62
(d) 64
► (a) 63
5. As we move from left to right in a period in modern periodic table, Atomic sizes of the elements generally
(a) increase
(b) decrease
(c) remain same
(d) approach zero
► (b) decrease
6. Newlands relation is called
(a) Musical Law
(b) Law of Octaves
(c) Periodic Law
(d) Atomic Mass Law
► (b) Law of Octaves
7. The arrangement of elements in the Modem Periodic Table is based on their
(a) increasing atomic mass in the period
(b) increasing atomic number in the horizontal rows
(c) increasing atomic number in the vertical columns
(d) increasing atomic mass in the group
► (b) increasing atomic number in the horizontal rows
8. An atom of an element has the electronic confi-guration 2,8,2. To which group does it belong?
(a) 4th group
(b) 6th group
(c) 3rd group
(d) 2nd group
► (d) 2nd group
9. Carbon belongs to the second period and Group 14. Silicon belongs to the third period and Group 14. If atomic number of carbon is 6, the atomic number of silicon is
(a) 7
(b) 14
(c) 24
(d) 16
► (b) 14
10. Where would you locate the element with electronic configuration 2, 8 in the Modern Periodic Table?
(a) Group 8
(b) Group 2
(c) Group 18
(d) Group 10
► (c) Group 18
11. 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?
(a) Chlorine
(b) Silicon
(c) Oxygen
(d) Germanium
► (d) Germanium
12. What is the atomic number of element of period 3 and group 17 of the Periodic Table?
(a) 10
(b) 4
(c) 17
(d) 21
► (c) 17
13. The law of the modern periodic table was proposed by:
(a) H.G.I Moselly
(b) Dobereincer
(c) D.I. Mendeleev
(d) Newlands
► H.G.I Moselly
14. Pick out the chemically most reactive elements from the given triads.
Li, Na, K F, Cl, Br
(a) Li and F
(b) Li and Br
(c) K and F
(d) K and Br
► (c) K and F
15. The elements A, B and C belong to groups 1, 14 and 17 respectively of the Periodic Table. Which two elements will form ionic compounds?
(a) A and B
(b) A and C
(c) B and C
(d) None
► (b) A and C
16. Element X forms a chloride with the formula XCl2, which is a solid with high melting point. X would most likely be:
(a) Si
(b) Al
(c) Na
(d) Mg
► (d) Mg
► (d) Mg
17. Which one of the following statements is not correct about the trends in the properties of the elements of a period on going from left to right?
(a) The oxides become more acidic
(b) The elements become less metallic
(c) There is an increase in the number of valence electrons
(d) The atoms lose their electrons more easily
► (d) The atoms lose their electrons more easily
18. Dobereiner’s triad arranged the elements with similar properties into:
(a) Periods
(b) Groups
(c) Both period and group
(d) None of these
► (b) Groups
19. Name the neutral atom in the Periodic Table which has the same number of electrons as K+ and Cl-.
(a) Helium
(b) Argon
(c) Neon
(d) Krypton
► (b) Argon
20. Which of the following is the outermost shell for elements of second period?
(a) K shell
(b) L shell
(c) M shell
(d) N shell
► (b) L shell
21. An element X has mass number 40 and contains 21 neutrons in its atom. To which group of the Periodic Table does it belong?
(a) Group 1
(b) Group 4
(c) Group 2
(d) Group 3
► (a) Group 1
22. An element ‘A’ belongs to the third period and group 16 of the Periodic Table. Find out the valency of A.
(a) Valency = 6
(b) Valency = 2
(c) Valency = 1
(d) Valency = 3
► (b) Valency = 2
23. How many elements are placed in lanthanide and actinide series?
(a) 57, 89
(b) 14, 14
(c) 89, 57
(d) 14, 16
► (b) 14, 14
24. An element X combines with oxygen to form an oxide XO. This oxide is electrically conducting. Write the formula of the compound formed when X reacts with chlorine.
(a) XCl3
(b) XCl
(c) XCl2
(d) XCl5
► (c) XCl2
25. Which of the following elements of noble gases participate in chemical reaction?
► (c) XCl2
25. Which of the following elements of noble gases participate in chemical reaction?
(a) Kr, Rn
(b) He, Kr
(c) Rn, He
(d) He, Ne
► (a) Kr, Rn
26. Which one of the following statements is not correct about the trends in the properties of the elements of a group on going down in a group?
(a) The chemical reactivity of metals increases.
(b) The metallic character of elements increases.
(c) The size of the atom increases.
(d) The valence electrons increase.
► (d) The valence electrons increase.
27. The element which has least tendency to lose electron is
(a) H
(b) Li
(c) He
(d) Ne
► (c) He
28. An element has 12 protons. The group and period to which this element belongs to is
(a) 2nd group, 3rd period
(b) 2nd group, 2nd period
(c) 3rd group, 2nd period
(d) 3rd group, 3rd period
► (a) 2nd group, 3rd period
29. The metal which is hard and has high melting point and used in filaments of electrical bulbs is
(a) Ni
(b) Fe
(c) Pt
(d) W
► (d) W
30. The non-metals are present:
(a) On the right hand side of the periodic table.
(b) In the middle of the periodic table.
(c) In the centre of the periodic table.
(d) On the left hand side of the periodic table.
► (a) On the right hand side of the periodic table.
31. Mendeleev’s classification was based on _______ .
(a) Increasing atomic mass
(b) Decreasing atomic number
(c) Increasing atomic number
(d) Decreasing atomic mass
► (a) Increasing atomic mass
32. Which of the following set of elements is written in order of their increasing metallic character?
(a) Na Li K
(b) C Q N
(c) Mg Al Si
(d) Be Mg Ca
► (d) Be Mg Ca
33. The elements of group 16 are called
(a) Chalcogens
(b) Halogens
(c) Pnicogens
(d) Noble gases
► (a) Chalcogens
34. 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 ? [NCERT Exemplar Problems]
(a) Germanium
(b) Chlorine
(c) Oxygen
(d) Silicon
► (a) Germanium
35. Nitrogen and phosphorus belong to the group 15 of the periodic table. Which of these will be more electronegative?
(a) Phosphorus
(b) Both are equally electronegative
(c) Nitrogen
(d) None of these
► (c) Nitrogen
36. Modern Periodic law is based upon:
(a) Number of neutrons
(b) Number of electron
(c) Atomic number
(d) Atomic mass
► (c) Atomic number
37. Which one of the following elements exhibit the maximum number of valence electrons?
(a) Na
(b) Al
(c) Si
(d) P
► (d) P
38. Which of the following statements about the Modern Periodic Table is correct?
(a) It has 18 horizontal rows known as Periods
(b) It has 7 vertical columns known as Periods
(c) It has 18 vertical columns known as Groups
(d) It has 7 horizontal rows known as Groups
► (c) It has 18 vertical columns known as Groups
39. Upto which element, the Law of Octaves was found to be applicable:
(a) Oxygen
(b) Calcium
(c) Cobalt
(d) Potassium
► (b) Calcium
40. Which of the following is most reactive
(a) F2
(b) Cl2
(c) Br2
(d) I2
► (a) F2
41. Chlorine (17) belongs to which group and period
(a) 7, 3
(b) 17, 3
(c) 1, 3
(d) 16, 3
► (b) 17, 3
► (a) F2
41. Chlorine (17) belongs to which group and period
(a) 7, 3
(b) 17, 3
(c) 1, 3
(d) 16, 3
► (b) 17, 3
42. An element has an atomic number of 15 with which of the following elements will it show similar chemical properties.
(a) Be (4)
(b) Ne (10)
(c) N (7)
(d) O (8)
► (c) N (7)
43. Which of the following sets of elements do not belong to the same group?
(a) F, Cl, Br
(b) Na, K, Rb
(c) P, S, Cl
(d) C, Si, Ge
► (c) P, S, Cl
44. What is the basis of long form of the periodic table?
(a) Atomic mass
(b) Atomic number
(c) Atomic size
(d) Metallic and Non-metallic character
► (b) Atomic number
45. Silicon(14) belongs to class of
(a) Metal
(b) Non-metal
(c) Metalloids
(d) Ionic compound
► (c) Metalloids
46. Which of the following is most reactive
(a) Li
(b) H
(c) Na
(d) K
► (d) K
47. The element with atomic number 14 is hard and forms acidic oxide and a covalent halide. To which of the following categories does the element belong?
(a) Metal
(b) Metalloid
(c) Non-metal
(d) Left-hand side element
► (b) Metalloid
48. Assertion: Fluorine is more reactive than chlorine.
Reason: Fluorine and chlorine belong to Group 17 called Halogen.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
(e) Both A and R are false.
► (b) Both A and R are true but R is not the correct explanation of A.
49. Assertion: There are 118 elements dis-covered so far.
Reason: Sulphur (16) belongs to Group 16 and belongs to 3rd period.
► (b) Both A and R are true but R is not the correct explanation of A.
49. Assertion: There are 118 elements dis-covered so far.
Reason: Sulphur (16) belongs to Group 16 and belongs to 3rd period.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
(e) Both A and R are false.
► (b) Both A and R are true but R is not the correct explanation of A.
50. Assertion: K is more reactive than Na.
Reason: K is smaller in size than Na.
► (b) Both A and R are true but R is not the correct explanation of A.
50. Assertion: K is more reactive than Na.
Reason: K is smaller in size than Na.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
(e) Both A and R are false.
► (c) A is true but R is false.
► (c) A is true but R is false.