ROUTERA


Chapter 7 The p- Block Elements

Class 12th Chemistry Chapter MCQs


1. Which of the following elements is a p-block element?

a) Sodium
b) Magnesium
c) Nitrogen
d) Calcium
Answer: c) Nitrogen
Explanation: Nitrogen is a p-block element, while Sodium, Magnesium, and Calcium are s-block elements.


2. Which of the following is the most electronegative element in the p-block?

a) Chlorine
b) Oxygen
c) Fluorine
d) Nitrogen
Answer: c) Fluorine
Explanation: Fluorine is the most electronegative element in the periodic table.


3. The acidic nature of oxides of p-block elements generally increases from

a) Left to right across a period
b) Top to bottom in a group
c) Right to left across a period
d) Bottom to top in a group
Answer: a) Left to right across a period
Explanation: The acidic nature of oxides increases as we move from left to right across a period in the p-block.


4. Which of the following is a noble gas?

a) Neon
b) Nitrogen
c) Phosphorus
d) Oxygen
Answer: a) Neon
Explanation: Neon is a noble gas in the p-block, while nitrogen, phosphorus, and oxygen are not.


5. Which of the following is a characteristic of group 17 elements?

a) They are highly electropositive
b) They have low melting points
c) They form covalent bonds
d) They are metals
Answer: c) They form covalent bonds
Explanation: Group 17 elements (halogens) form covalent bonds with other non-metals.


6. Which of the following elements exhibits the highest oxidation state?

a) Carbon
b) Oxygen
c) Nitrogen
d) Fluorine
Answer: d) Fluorine
Explanation: Fluorine exhibits the highest oxidation state of +7 in compounds like OF₇.


7. Which of the following halogens is the most reactive?

a) Chlorine
b) Fluorine
c) Bromine
d) Iodine
Answer: b) Fluorine
Explanation: Fluorine is the most reactive halogen due to its high electronegativity.


8. Which of the following is the most stable oxidation state of nitrogen?

a) +3
b) +5
c) +2
d) +4
Answer: a) +3
Explanation: The most stable oxidation state of nitrogen is +3, as seen in compounds like NCl₃.


9. Which of the following is a property of noble gases?

a) They are highly reactive
b) They have low ionization enthalpies
c) They form compounds with oxygen
d) They are inert and do not easily form compounds
Answer: d) They are inert and do not easily form compounds
Explanation: Noble gases are chemically inert due to their complete outer electron shells.


10. Which of the following compounds is formed by the reaction of phosphorus with oxygen?

a) Phosphine
b) Phosphorus pentachloride
c) Phosphorus pentoxide
d) Phosphorus trichloride
Answer: c) Phosphorus pentoxide
Explanation: Phosphorus pentoxide (P₄O₁₀) is formed when phosphorus reacts with oxygen.


11. Which of the following is the correct order of electronegativity for the elements in group 15?

a) Nitrogen > Phosphorus > Arsenic > Antimony > Bismuth
b) Bismuth > Antimony > Arsenic > Phosphorus > Nitrogen
c) Nitrogen > Phosphorus > Antimony > Arsenic > Bismuth
d) Nitrogen > Phosphorus > Arsenic > Bismuth > Antimony
Answer: a) Nitrogen > Phosphorus > Arsenic > Antimony > Bismuth
Explanation: Electronegativity decreases as we move down the group in the p-block.


12. Which of the following halogen compounds is commonly used as a disinfectant?

a) Hydrogen chloride
b) Chlorine
c) Bromine
d) Iodine
Answer: b) Chlorine
Explanation: Chlorine is commonly used as a disinfectant, especially in water treatment.


13. The anion of which element is commonly used in the preparation of bleach?

a) Fluorine
b) Chlorine
c) Bromine
d) Iodine
Answer: b) Chlorine
Explanation: Chlorine is used in the preparation of sodium hypochlorite, commonly known as bleach.


14. Which of the following is the correct oxidation state of chlorine in potassium chloride (KCl)?

a) +1
b) +2
c) -1
d) 0
Answer: c) -1
Explanation: Chlorine in KCl has an oxidation state of -1, as it gains one electron.


15. Which of the following elements shows the maximum oxidation state in its compounds?

a) Carbon
b) Nitrogen
c) Oxygen
d) Fluorine
Answer: d) Fluorine
Explanation: Fluorine shows the maximum oxidation state of +7 in compounds like OF₇.


16. The noble gases have a unique property of not forming compounds because they:

a) Have a complete octet in their valence shell
b) Are highly electronegative
c) Have very low ionization energy
d) Have a high melting point
Answer: a) Have a complete octet in their valence shell
Explanation: Noble gases have full outer electron shells, making them chemically inert and not reactive.


17. The compound BCl₃ (boron trichloride) exhibits which of the following types of bonding?

a) Ionic bonding
b) Covalent bonding
c) Metallic bonding
d) Coordinate bonding
Answer: b) Covalent bonding
Explanation: Boron trichloride is a covalent compound, as boron and chlorine both share electrons.


18. The electronegativity of fluorine is:

a) 2.5
b) 3.5
c) 4.0
d) 3.0
Answer: c) 4.0
Explanation: Fluorine has the highest electronegativity value of 4.0 in the periodic table.


19. Which of the following elements is a part of group 16 of the p-block?

a) Nitrogen
b) Oxygen
c) Carbon
d) Phosphorus
Answer: b) Oxygen
Explanation: Oxygen is a group 16 element, also known as the chalcogens.


20. The least electronegative element among the halogens is:

a) Fluorine
b) Chlorine
c) Bromine
d) Iodine
Answer: d) Iodine
Explanation: Iodine is the least electronegative halogen because electronegativity decreases down the group.


21. Which of the following halogen oxides is stable under normal conditions?

a) Cl₂O
b) ClO₂
c) I₂O₅
d) I₂O₇
Answer: b) ClO₂
Explanation: Chlorine dioxide (ClO₂) is stable under normal conditions, whereas other halogen oxides are highly reactive.


22. Which of the following is the correct oxidation state of nitrogen in nitric acid (HNO₃)?

a) +5
b) +3
c) +1
d) +4
Answer: a) +5
Explanation: In nitric acid, nitrogen has an oxidation state of +5.


23. Which of the following elements shows the highest oxidation state of +4 in its compounds?

a) Carbon
b) Silicon
c) Germanium
d) Lead
Answer: b) Silicon
Explanation: Silicon shows the highest oxidation state of +4 in its compounds, such as SiO₂.


24. Which of the following p-block elements forms an amphoteric oxide?

a) Aluminum
b) Magnesium
c) Sodium
d) Potassium
Answer: a) Aluminum
Explanation: Aluminum oxide (Al₂O₃) is amphoteric, meaning it can react with both acids and bases.


25. Which of the following compounds of phosphorus is used as a flame retardant?

a) Phosphoric acid
b) Phosphorus pentachloride
c) Red phosphorus
d) White phosphorus
Answer: c) Red phosphorus
Explanation: Red phosphorus is used in flame retardants and matches due to its stability.


26. Which of the following has the highest ionization energy in the p-block?

a) Nitrogen
b) Oxygen
c) Fluorine
d) Neon
Answer: c) Fluorine
Explanation: Fluorine has the highest ionization energy among the given elements due to its small size and high electronegativity.


27. Which of the following elements forms a compound with oxygen where the oxygen is in the -2 oxidation state?

a) Nitrogen
b) Phosphorus
c) Oxygen
d) Fluorine
Answer: c) Oxygen
Explanation: In oxides, oxygen typically has an oxidation state of -2, as in O₂.


28. Which of the following elements does not form a stable cation?

a) Aluminum
b) Boron
c) Nitrogen
d) Oxygen
Answer: c) Nitrogen
Explanation: Nitrogen does not form a stable cation due to its high electronegativity and small size.


29. Which of the following p-block elements is used in the production of fertilizers?

a) Nitrogen
b) Phosphorus
c) Potassium
d) All of the above
Answer: d) All of the above
Explanation: Nitrogen, phosphorus, and potassium are all key elements in fertilizers.


30. Which of the following compounds of chlorine is used as a disinfectant?

a) Chlorine water
b) Chlorine dioxide
c) Sodium hypochlorite
d) Hydrogen chloride
Answer: c) Sodium hypochlorite
Explanation: Sodium hypochlorite (NaOCl) is used as a disinfectant in bleach.


31. Which of the following compounds is formed by the reaction of sulfur with oxygen?

a) Sulfur dioxide
b) Sulfur hexafluoride
c) Sulfuric acid
d) Sulfur monoxide
Answer: a) Sulfur dioxide
Explanation: Sulfur dioxide (SO₂) is formed when sulfur reacts with oxygen.


32. Which of the following elements is commonly used in the production of semiconductors?

a) Silicon
b) Phosphorus
c) Nitrogen
d) Carbon
Answer: a) Silicon
Explanation: Silicon is widely used in the production of semiconductors due to its electrical properties.


33. Which of the following p-block elements is most likely to form an ionic bond with sodium?

a) Nitrogen
b) Phosphorus
c) Oxygen
d) Fluorine
Answer: d) Fluorine
Explanation: Fluorine has a high electronegativity and readily forms ionic bonds with sodium.


34. Which of the following halogen compounds is most reactive?

a) Iodine pentafluoride
b) Chlorine trifluoride
c) Fluorine
d) Bromine
Answer: b) Chlorine trifluoride
Explanation: Chlorine trifluoride (ClF₃) is highly reactive due to its strong oxidizing nature.


35. Which of the following is the correct order of electronegativity of the elements in group 16?

a) Oxygen > Sulfur > Selenium > Tellurium > Polonium
b) Oxygen > Sulfur > Tellurium > Selenium > Polonium
c) Polonium > Tellurium > Selenium > Sulfur > Oxygen
d) Oxygen > Selenium > Tellurium > Sulfur > Polonium
Answer: a) Oxygen > Sulfur > Selenium > Tellurium > Polonium
Explanation: Electronegativity decreases as we move down group 16.


36. Which of the following is a property of group 17 elements?

a) They are non-metals
b) They are highly electropositive
c) They are good conductors of electricity
d) They have high melting points
Answer: a) They are non-metals
Explanation: Group 17 elements, known as halogens, are non-metals and tend to form covalent bonds.


37. Which of the following elements is essential for the formation of proteins?

a) Nitrogen
b) Phosphorus
c) Silicon
d) Fluorine
Answer: a) Nitrogen
Explanation: Nitrogen is a crucial element in amino acids, which form proteins.


38. Which of the following p-block elements is most likely to form an oxide with the formula XO₂?

a) Nitrogen
b) Oxygen
c) Phosphorus
d) Chlorine
Answer: c) Phosphorus
Explanation: Phosphorus forms an oxide with the formula P₂O₅, which contains XO₂ units.


39. Which of the following compounds is an example of an interhalogen compound?

a) Iodine monochloride
b) Sodium chloride
c) Calcium fluoride
d) Ammonium chloride
Answer: a) Iodine monochloride
Explanation: Interhalogen compounds are formed by combining two halogens, such as iodine monochloride (ICl).


40. Which of the following oxides is amphoteric?

a) Al₂O₃
b) Na₂O
c) SO₃
d) CO₂
Answer: a) Al₂O₃
Explanation: Aluminum oxide (Al₂O₃) is amphoteric, meaning it reacts with both acids and bases.


41. Which of the following p-block elements is associated with the formation of acid rain?

a) Nitrogen
b) Phosphorus
c) Sulfur
d) Oxygen
Answer: c) Sulfur
Explanation: Sulfur dioxide (SO₂) and sulfur trioxide (SO₃) contribute to the formation of acid rain.


42. Which of the following is a property of the noble gases?

a) High ionization enthalpy
b) Low boiling point
c) High reactivity
d) High electronegativity
Answer: a) High ionization enthalpy
Explanation: Noble gases have high ionization enthalpies due to their stable electron configurations.


43. Which of the following halogens forms the most stable diatomic molecule?

a) Fluorine
b) Chlorine
c) Bromine
d) Iodine
Answer: a) Fluorine
Explanation: Fluorine (F₂) forms the most stable diatomic molecule due to its high bond energy.


44. Which of the following is the most common oxidation state of phosphorus in its compounds?

a) +3
b) +5
c) +2
d) -3
Answer: b) +5
Explanation: Phosphorus commonly exhibits the +5 oxidation state in compounds like P₄O₁₀.


45. Which of the following elements forms an oxide that is acidic in nature?

a) Nitrogen
b) Phosphorus
c) Sulfur
d) All of the above
Answer: d) All of the above
Explanation: All these elements form acidic oxides like NO₂, P₂O₅, and SO₃.


46. Which of the following is the correct formula of phosphorus pentachloride?

a) PCl₃
b) PCl₅
c) P₄Cl₃
d) P₂Cl₅
Answer: b) PCl₅
Explanation: The formula of phosphorus pentachloride is PCl₅.


47. Which of the following elements does not form a stable +5 oxidation state?

a) Nitrogen
b) Phosphorus
c) Arsenic
d) Antimony
Answer: a) Nitrogen
Explanation: Nitrogen does not form a stable +5 oxidation state in most of its compounds.


48. Which of the following halogens can form the maximum number of compounds with oxygen?

a) Fluorine
b) Chlorine
c) Bromine
d) Iodine
Answer: a) Fluorine
Explanation: Fluorine can form a wide variety of compounds with oxygen due to its high electronegativity.


49. Which of the following elements is most likely to form a covalent bond with carbon?

a) Oxygen
b) Nitrogen
c) Phosphorus
d) Fluorine
Answer: a) Oxygen
Explanation: Oxygen is most likely to form a covalent bond with carbon due to its electronegativity.


50. Which of the following elements forms a compound that is used in the manufacture of fertilizers?

a) Phosphorus
b) Nitrogen
c) Potassium
d) All of the above
Answer: d) All of the above
Explanation: Nitrogen, phosphorus, and potassium are essential components in fertilizers.