9th class Chemistry, Chapter 9: Group Properties and Elements MCQs

1. Which halogen will have the least reactivity with alkaline earth metals?

1. (A) Chlorine
2. (B) Iodine ✓
3. (C) Bromine
4. (D) Fluorine

2. Which compound do you expect to be coloured?

1. (A) KCl
2. (B) BaCl₂
3. (C) AlCl₃
4. (D) NiCl₂ ✓

3. In which element there exists the strongest forces of attraction between atoms?

1. (A) Mg ✓
2. (B) Ca
3. (C) Sr
4. (D) Ba

4. Elements of which group are all coloured?

1. (A) Second group
2. (B) Sixth group ✓
3. (C) Fourth group
4. (D) Fifth group

5. Which halogen acid is unstable at room temperature?

1. (A) HBr
2. (B) HI ✓
3. (C) HCl
4. (D) HF

6. Which oxide is the most basic oxide?

1. (A) Na₂O ✓
2. (B) Li₂O
3. (C) MgO
4. (D) CO

7. Which group elements are the most reactive elements?

1. (A) Transition metal group
2. (B) First group ✓
3. (C) Second group
4. (D) Third group

8. The following solutions of a halogen and a sodium halide are mixed together. Which solution will turn dark because of a reaction?

1. (A) Br₂ and NaCl
2. (B) Br₂ and NaF
3. (C) Cl₂ and NaF
4. (D) Cl₂ and NaI ✓

9. X is a monoatomic gas, which statement about this is correct?

1. (A) X burns in air
2. (B) X is coloured
3. (C) X is unreactive ✓
4. (D) X will displace iodine from it

10. Which property is correct for group 1 elements?

1. (A) Low catalytic activity ✓
2. (B) High density
3. (C) Low electrical conductivity
4. (D) High melting point

11. The outer electronic configuration of alkali metals is:

1. (A) ns²np⁵
2. (B) ns¹ ✓
3. (C) ns²
4. (D) ns²np¹

12. The first element of group 1 which is a gas and a non-metal is:

1. (A) Helium
2. (B) Sodium
3. (C) Hydrogen ✓
4. (D) Lithium

13. Which alkali metal reacts violently with water?

1. (A) None of them
2. (B) Potassium ✓
3. (C) Lithium
4. (D) Sodium only

14. Which alkali metal sinks in water?

1. (A) Lithium
2. (B) Sodium
3. (C) Potassium
4. (D) Rubidium ✓

15. The melting point of sodium is:

1. (A) 64 °C
2. (B) 28 °C
3. (C) 98 °C ✓
4. (D) 180 °C

16. The density of caesium is:

1. (A) 0.97 g/cm³
2. (B) 0.86 g/cm³
3. (C) 1.87 g/cm³ ✓
4. (D) 0.53 g/cm³

17. Down group 1 the melting points:

1. (A) First increase then decrease
2. (B) Decrease ✓
3. (C) Increase
4. (D) Remain same

18. Lithium reacts with water to give hydrogen and:

1. (A) Lithium hydroxide ✓
2. (B) Lithium oxide
3. (C) Lithium chloride
4. (D) Lithium carbonate

19. Halogens exist as:

1. (A) Monoatomic atoms
2. (B) Triatomic molecules
3. (C) Ionic crystals
4. (D) Diatomic molecules ✓

20. Chlorine gas is:

1. (A) Pale yellow
2. (B) Red-brown
3. (C) Colourless
4. (D) Yellowish green ✓