Periodic Table & Periodicity MCQs: Groups, Periods, and Classification of Elements

Introduction: Welcome to this MCQ set on Groups, Periods, and Classification of Elements. This topic is essential for understanding the structure of the periodic table, trends, and properties of elements. Test your understanding, then check the answer key at the end.

1. The periodic table is divided into how many groups?
   (a) 7
   (b) 8
   (c) 16
   (d) 18
   
2. How many periods are present in the modern periodic table?
   (a) 6
   (b) 7
   (c) 8
   (d) 10
   
3. What is the total number of elements in period 2 of the periodic table?
   (a) 2
   (b) 6
   (c) 8
   (d) 18
   
4. Which element is placed at the top of Group 1 in the modern periodic table?
   (a) Helium
   (b) Hydrogen
   (c) Lithium
   (d) Sodium
   
5. Which of the following elements belongs to Group 17?
   (a) Oxygen
   (b) Nitrogen
   (c) Fluorine
   (d) Magnesium
   
6. The noble gases belong to which group in the periodic table?
   (a) Group 16
   (b) Group 17
   (c) Group 18
   (d) Group 19
   
7. Elements in the same group of the periodic table have:
   (a) The same atomic number
   (b) The same number of valence electrons
   (c) The same number of protons
   (d) The same atomic size
   
8. The number of valence electrons in alkali metals (Group 1) is:
   (a) 1
   (b) 2
   (c) 3
   (d) 4
   
9. Which of the following elements is a transition metal?
   (a) Sodium (Na)
   (b) Iron (Fe)
   (c) Neon (Ne)
   (d) Sulfur (S)
   
10. The lanthanides and actinides are placed separately in the periodic table because:
    (a) They do not fit in the main body of the table
    (b) They are radioactive
    (c) They have the same atomic number
    (d) They are noble gases
    
11. Which block of the periodic table contains the transition metals?
    (a) s-block
    (b) p-block
    (c) d-block
    (d) f-block
    
12. Which of the following elements is an inner transition metal?
    (a) Magnesium (Mg)
    (b) Gold (Au)
    (c) Uranium (U)
    (d) Chlorine (Cl)
    
13. The period number of an element represents:
    (a) The number of valence electrons
    (b) The number of electron shells
    (c) The atomic mass
    (d) The number of neutrons
    
14. Which group of elements is also known as the halogens?
    (a) Group 1
    (b) Group 2
    (c) Group 17
    (d) Group 18
    
15. Which group contains elements that are highly reactive and form salts with halogens?
    (a) Group 1 (Alkali metals)
    (b) Group 2 (Alkaline earth metals)
    (c) Group 16
    (d) Group 18 (Noble gases)
    
16. Which element is a metalloid?
    (a) Sodium (Na)
    (b) Boron (B)
    (c) Neon (Ne)
    (d) Calcium (Ca)
    
17. What is the main characteristic of noble gases?
    (a) Highly reactive
    (b) Chemically inert
    (c) Metallic in nature
    (d) High electronegativity
    
18. Which of the following is a property of transition metals?
    (a) Low density
    (b) Good conductivity
    (c) Very low melting point
    (d) Always colorless compounds
    
19. Which element is in the same group as carbon (C)?
    (a) Sodium (Na)
    (b) Silicon (Si)
    (c) Iron (Fe)
    (d) Chlorine (Cl)
    

Answer Key

1. (d) The periodic table has 18 groups.
2. (b) There are 7 periods in the periodic table.
3. (c) Period 2 contains 8 elements.
4. (b) Hydrogen is placed at the top of Group 1.
5. (c) Fluorine belongs to Group 17 (halogens).
6. (c) Noble gases are in Group 18.
7. (b) Elements in the same group have the same number of valence electrons.
8. (a) Alkali metals have 1 valence electron.
9. (b) Iron (Fe) is a transition metal.
10. (a) Lanthanides and actinides do not fit in the main table structure.
11. (c) Transition metals are in the d-block.
12. (c) Uranium (U) is an inner transition metal.
13. (b) Period number = number of electron shells.
14. (c) Halogens belong to Group 17.
15. (a) Alkali metals form salts with halogens.
16. (b) Boron (B) is a metalloid.
17. (b) Noble gases are chemically inert.
18. (b) Transition metals conduct electricity well.
19. (b) Silicon (Si) is in the same group as carbon.