Chemistry Multiple Choice Questions on “P-Block Elements – Interhalogen Compounds”.
1. Which is the least basic trihalide of nitrogen?
a) NI3
b) NBr3
c) NCl3
d) NF3
Answer: d
Clarification: NF3 is the least basic trihalide of nitrogen because it has different size and the bond ismorepolar towards nitrogen as it is more electronegative than the remaining halides, which makes electron availabilitymoreon nitrogen(in NF3) than the remaining halides. Thus, it can donate electrons easily and therefore NF3 is least basic.
2. Which of the following is true about interhalogen compounds?
a) They have unpaired electrons
b) They are highly stable
c) They are diamagnetic
d) They are paramagnetic
Answer: c
Clarification: Interhalogen compounds are diamagnetic in nature. This is because they have bond pairs and lone pairs. The A-X bond in interhalogen compounds is much weaker than the X-X bond in halogens, except for the F-F bond.
3. What do asthma patients use for respiration?
a) O2 and H2
b) O2 and He
c) O2 and Ar
d) O2 and Ne
Answer: b
Clarification: Helium-Oxygen (80:20 or 70:30) mixture provides a dramatic benefit for asthma patients with severe exacerbations. Helium is about 10% as dense as room air and, consequently, travels more easily down narrowed passages.
4. Interhalogen compounds are more reactive than halogen compounds.
a) True
b) False
Answer: a
Clarification: Interhalogen compounds are formed by ionic bonds due to differences in electronegativity. They are more reactive because they can dissociate easily as they have weaker bonds as compared to pure halogen compounds possessing covalent bonds that are formed by the sharing of electrons.
5. Which is the correct statement regarding halogens?
a) They are not all diatomic and form univalent ions
b) They are all diatomic and do not form univalent ions
c) They are all diatomic and form univalent ions
d) They are all diatomic and form bivalent ions
Answer: c
Clarification: Halogens are all diatomic and form univalent ions. All halogens can act as both oxidizing and reducing agents and are capable of exhibiting more than one stable oxidation state except Fluorine. Hence, option c is the correct statement.
6. Xenon fluorides are reactive.
a) True
b) False
Answer: b
Clarification: Fluorine is the most electronegative element and is a very powerful oxidising agent. Although generally unreactive, xenon reacts with fluorine and gets oxidised forming fluorides of the type XeF2, XeF4 and XeF6. These fluorides not reactive.
7. What is the hybridization of interhalogen compounds of the type XX’3 (Bent T-shaped)?
a) sp3d2
b) sp
c) sp3d
d) sp2
Answer: c
Clarification: The structure of all interhalogen compounds of the type XX’3 involves sp3d hybridization of the central atom X and hence they have trigonal bipyramidal geometries or T-shaped molecules (also called as see-saw).
8. What are interhalogen compounds used as?
a) Reducing agents
b) Aqueous solvents
c) To decreasing reactivity
d) Non-aqueous solvents
Answer: d
Clarification: If we come to the uses of the interhalogen compounds, then one of its main uses is to act as the halogenating agent, i.e., they are used to form other halogen compounds like BrF5. Interhalogen compounds of fluorine are very useful fluorinating agents.
9. Why is helium added to oxygen which is used by deep-sea divers?
a) It is immiscible with oxygen
b) It is miscible with oxygen
c) It is less soluble in blood
d) It is less poisonous
Answer: c
Clarification: Air contains a large amount of nitrogen. According to Henry’s law, the solubility of gases increases with increase in pressure. Due to the increased pressure, a large amount of nitrogen dissolves in the blood of a deep-sea diver. To prevent this, helium is added to the oxygen cylinders as it is sparingly less soluble in blood.
10. What is the hybridization of interhalogen compounds of the type XX’5(Square pyramidal)?
a) sp3d2
b) sp2d2
c) sp4d3
d) sp3d3
View Answer
Answer: a
Clarification: The structure of all interhalogen compounds of the type XX’5 involves sp3d2 hybridization of the central halogen atom X and hence have octahedral (also called square pyramidal) geometry and with one position occupied by a lone pair.