JEE Chemistry The P Block Elements MCQs Set E

Question. Argon is used
(a) in high temperature welding
(b) in radiotherapy for treatment of cancer
(c) to obtain low temperature
(d) in filling airships

Answer: A

Question. Which one of the following statements regarding helium isincorrect ?
(a) It is used to fill gas balloons instead of hydrogen because it is lighter and non-inflammable
(b) It is used to produce and sustain powerful superconducting magnets
(c) None of these
(d) It is used in gas-cooled nuclear reactors.

Answer: A

Question. Noble gases are used in discharge tubes to gives different colours. Reddish orange glow is due to
(a) Ne
(b) Kr
(c) Ar
(d) Xe

Answer: A

Question. The coloured discharge tubes for advertisement mainly contain
(a) neon
(b) xenon
(c) helium
(d) argon

Answer: A

Question. Sea divers go deep in the sea water with a mixture of which of the following gases
(a) O₂ and He
(b) O₂ and CO₂
(c) O₂ and Ar
(d) None of  these

Answer: A

Question. Which of the following is the life saving mixture for an asthma patient ?
(a) Mixture of helium and oxygen
(b) Mixture of neon and oxygen
(c) Mixture of xenon and nitrogen
(d) Mixture of argon and oxygen

Answer: A

Question. Which of the following statements are true?
(i) Only type of interactions between particles of noble gases are due to weak dispersion forces.
(ii) Ionisation enthalpy of molecular oxygen is very close to that of xenon.
(iii) Hydrolysis of XeF₆ is redox reaction.
(iv) Xenon fluorides are not reactive.
(a) (i) and (ii)
(b) (iii) and (iv)
(c) (i) and (iii)
(d) (ii) and (iii)

Answer: A

Question. Which of the following element has the property of diffusing through most commonly used laboratory materials such as rubber, glass or plastics
(a) He
(b) Xe
(c) Rn
(d) Ar

Answer: A

Question. Which of the following is used to produce and sustain powerful superconducting magnets to form an essential part of NMR spectrometer
(a) He
(b) Ne
(c) Ar
(d) Rn

Answer: A

Question. Which of the following statements are correct?
(i) Arsenic and antimony are metalloids.
(ii) Phosphorus, arsenic and antimony are found mainly as sulphide minerals.
(iii) Covalent redii increases equally from N to Bi.
(iv) Elements of group 15 have extra stability and higher ionisation energy due to exactly half filled ns²np³ electronic configuration.
(v) In group 15 elements only nitrogen is gas whereas all others are solids.
(a) (i), (iv) and (v)
(b) (i), (ii) and (iii)
(c) (ii), (iii) and (iv)
(d) (ii), (iii) and (v)

Answer: A

Question.
Assertion : Dinitrogen is inert at room temperature.
Reason : Dinitrogen directly combines with lithium to form ionic nitrides.
(a) Assertion is correct, reason is incorrect
(b) Assertion is incorrect, reason is correct
(c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
(d) Assertion is correct, reason is correct; reason is a correct explanation for assertion

Answer: A

Question.
Assertion : When a metal is treated with conc. HNO₃ it generally yields a nitrate, NO₂ and H₂O.
Reason : Conc. HNO₃ reacts with metal and first produces a metal nitrate and nascent hydrogen. The nascent hydrogen then further reduces HNO₃ to NO₂.
(a) Assertion is correct, reason is correct; reason is a correct explanation for assertion
(b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
(c) Assertion is correct, reason is incorrect
(d) Assertion is incorrect, reason is correct

Answer: A

Question.
Assertion : N₂ is less reactive than P₄.
Reason : Nitrogen has more electron gain enthalpy than phosphorus.
(a) Assertion is correct, reason is incorrect
(b) Assertion is incorrect, reason is correct
(c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
(d) Assertion is correct, reason is correct; reason is a correct explanation for assertion

Answer: A

Question.
Assertion : White phosphorus is more reactive than red phosphorus.
Reason : Red phosphorus consists of P₄ tetrahedral units linked to one another to form linear chains
(a) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
(b) Assertion is correct, reason is incorrect
(c) Assertion is incorrect, reason is correct
(d) Assertion is correct, reason is correct; reason is a correct explanation for assertion

Answer: A

Question.
Assertion : Bond angle of H₂S is smaller than H₂O.
Reason : Electronegativity of the central atom increases, bond angle decreases
(a) Assertion is correct, reason is incorrect
(b) Assertion is incorrect, reason is correct
(c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
(d) Assertion is correct, reason is correct; reason is a correct explanation for assertion.

Answer: A

Question. In nitrogen family, the H-M-H bond angle in the hydrides gradually becomes closer to 90º on going from N to Sb. This shows that gradually
(a) Almost pure p-orbitals are used for M-H bonding
(b) The bond energies of M-H bonds increase
(c) The bond pairs of electrons become nearer to the central atom
(d) The basic strength of the hydrides increases

Answer: A

Question. Concentrated nitric acid, upon long standing, turns yellow brown due to the formation of
(a) NO₂
(b) N₂O₄
(c) NO
(d) N₂O

Answer: C

Question. Ammonia on catalytic oxidation gives an oxide from which nitric acid is obtained. The oxide is
(a) NO₂
(b) N₂O₃
(c) NO
(d) N₂O₅

Answer: C

Question. What is the change observed when AgCl reacts with NH₃?
(a) Solution become colourless
(b) White ppt is formed
(c) Yellow ppt is formed
(d) No change is observed

Answer: A

Question. Electronegativity of oxygen is more than sulphur yet H₂S is acidic while water is neutral. This is because
(a) H–S bond is weaker than H–O bond
(b) H₂S is gas while H₂O is a liquid
(c) molecular mass of H₂S is more than H₂O
(d) water is highly associated compound

Answer: A

Question. It is possible to obtain oxygen from air by fractional distillation because
(a) oxygen has higher b.p. than nitrogen
(b) oxygen is more reactive than nitrogen
(c) oxygen is in a different group of the periodic table from nitrogen
(d) oxygen has a lower density than nitrogen

Answer: A

Question. The correct order of the thermal stability of hydrogen halides (H–X) is
(a) HF > HCl > HBr > HI
(b) HI > HCl < HF > HBr
(c) HCl< HF > HBr < HI
(d) HI < HBr > HCl < HF

Answer: A

Question. In the case of alkali metals, the covalent character decreases in the order
(a) MI > MBr > MCl > MF
(b) MF > MCl > MBr > MI
(c) MF > MCl > MI > MBr
(d) MCl > MI > MBr > MF

Answer: A

Question. Which pair gives Cl₂ at room temperature
(a) Conc. HCl + KMnO₄
(b) NaCl + MnO₂
(c) NaCl + Conc. HNO₃
(d) NaCl + Conc. H₂SO₄

Answer: A

Question. The elements which occupy the peaks of ionisation energy curve are
(a) He, Ne, Ar, Kr
(b) Na, Mg, Cl, I
(c) Na, K, Rb, Cs
(d) Cl, Br, I, F

Answer: A

Question. End-product of the hydrolysis of XeF₆ is
(a) XeO₃
(b) XeF₄O
(c) XeF₂O₂
(d) None of these

Answer: A