BITSAT Chemistry The P Block Elements (Group 15 16 17 And 18) MCQs

Question: Which of the following shows nitrogen with its increasing order of oxidation number?

a) NO < N₂O < NO₂ < NO₃^– < NH₄⁺

b) NH₄⁺ < N₂O < NO₂ < NO₃– < NO

c) NH₄⁺ < N₂O < NO < NO₂ < NO₃^–

d) NH₄⁺ < NO < N₂O < NO₂ < NO₃^–

Answer: NH₄⁺ < N₂O < NO < NO₂ < NO₃^–

Question: Which of these doesn’t exist?

a) PH₃

b) PH₅

c) LuH₃

d) PF₅

Answer: PH₅

Question: Laughing gas is

a) Nitrogen pentoxide

b) Nitrous oxide

c) Nitrogen trioxide

d) Nitric oxide

Answer: Nitrous oxide

Question: The by product of solvay-ammonia process is

a) CO₂

b) NH₃

c) CaCl₂

d) CaCO₃

Answer: CaCl₂

Question: Which of the following is a strong base?

a) PH₃

b) AsH₃

c) NH₃

d) SbH₃

Answer: NH₃

Question: Which of the following fluorides of xenon is impossible?

a) XeF₂

b) XeF₃

c) XeF₄

d) XeF₆

Answer: XeF₃

Question: Which of the following halogens exhibit only one oxidation state in its compounds ?

a) Bromine

b) Chlorine

c) Fluorine

d) Iodine

Answer: Fluorine

Question: Starch can be used as an indicator for the detection of traces of

a) Glucose in aqueous solution

b) Proteins in blood

c) Iodine in aqueous solution

d) Urea in blood

Answer: Iodine in aqueous solution

Question: Which one of the following arrangements represents the correct order of electron gain enthalpy (with negative sign) of the given atomic species?

a) S < O < Cl < F

b) Cl < F < S < O

c) F < Cl < O < S

d) O < S < F < Cl

Answer:  O < S < F < Cl

Question: Which of the following is incorrect with respect to property indicated ?

a) E.N : F > Cl > Br

b) E.A.: Cl > Br > < F

c) Oxidising power : F₂ > Cl₂ > Br₂

d) Bond energy : F₂ > Cl₂ > Br₂

Answer: Bond energy : F₂ > Cl₂ > Br₂

Question: Strong reducing behaviour of H₃PO₂ is due to

a) Presence of one –OH group and two P–H bonds

b) High electron gain enthalpy of phosphorus

c) High oxidation state of phosphorus

d) Presence of two –OH groups and one P–H bond

Answer: Presence of one –OH group and two P–H bonds

Question: When chlorine water is exposed to sunlight, O₂ is liberated. Hence

a) Hydrogen has little affinity to O₂

b) Hydrogen has more affinity to O₂

c) Hydrogen has more affinity to chlorine

d) It is a reducing agent

Answer: Hydrogen has more affinity to chlorine

Question: Phosphine is not obtained by the reaction

a) White P is heated with NaOH

b) Red P is heated with NaOH

c) Ca₃P₂ reacts with water

d) Phosphorus trioxide is boiled with water

Answer: Red P is heated with NaOH

Question: Which liberates ammonia when treated with water?

a) Li₃N

b) Mg₃N₂

c) CaCN₂

d) All

Answer: All

Question: The correct order of reactivity of halogens with alkalies is

a) F > Cl > Br > I

b) F < Cl > Br < I

c) F < Cl < Br < I

d) F < Cl < Br > I

Answer: F > Cl > Br > I

Question: Sodium pyrophosphate is

a) Na₂P₂O₇

b) Na₄P₂O₇

c) NaPO₄

d) Na₂PO₂

Answer: Na₄P₂O₇

Question: Bleaching action of SO₂ is due to its

a) Oxidising property

b) Acidic property

c) Reducing property

d) Basic property

Answer: Reducing property

Question: Which of the following behaves as both oxidising and reducing agents ?

a) H₂SO₄

b) SO₂

c) H₂S

d) HNO₃

Answer: SO₂

Question: Gradual addition of electronic shells in the noble gases causes a decrease in their

a) Lonization energy

b) Atomic radius

c) Boiling point

d) Density

Answer: Lonization energy

Question: Atomic radii of fluorine and neon in Angstrom units are respectively given by

a) 0.72 ; 1.60

b) 1.60 ; 1.60

c) 0.72 ; 0.72

d) None

Answer: 0.72 ; 1.60