Question 1

The boiling and melting points of the Group 18 elements&#10;A) decrease down the group&#10;B) increase down the group&#10;C) first increase for the three periods, then remain almost constant

Accepted Answer

The boiling and melting points of Group 18 elements (noble gases) increase down the group due to the increase in atomic size and the corresponding increase in van der Waals forces.

Question 2

What is one of the most frequent uses of the inert gases as a group?&#10;A) in light sources&#10;B) in spectroscopic imaging&#10;C) in breathing equipment (i.e. for divers and asthma patients)

Accepted Answer

Inert gases, such as neon, argon, and krypton, are commonly used in light sources, including neon lights and certain types of bulbs, due to their ability to produce light when electrically excited without reacting with other elements.

Question 3

Which oxidation state is not expected in xenon chemistry?&#10;A) +2&#10;B) +4&#10;C) +5

Accepted Answer

Xenon, a noble gas, typically exhibits oxidation states that are even numbers due to its electron configuration and the way it forms compounds. The +2, +4, and +8 oxidation states are observed in various xenon compounds, such as XeF2, XeF4, and XeF8, respectively. The +5 oxidation state is not expected or observed in xenon chemistry because it does not align with the typical electron sharing or transfer mechanisms seen in xenon compounds.

Question 4

Find the correct statement about the reaction conditions used in synthesis of xenon fluorides A) Decrease in pressure leads to formation of higher xenon fluorides B) Higher reaction pressures are required for the synthesis of XeF₆ than XeF₄. C) To prepare XeF₆, it is enough to expose a stoichiometric mixture of Xe and F₂ to light.

Accepted Answer

Higher reaction pressures favor the formation of xenon fluorides with more fluorine atoms, such as XeF6, compared to those with fewer fluorine atoms, like XeF4.

Question 5

Identify the correct statement(s):&#10;(i) Some xenon fluorides behave as Lewis acids.&#10;(ii) Xenon fluorides are starting materials used in synthesis of other xenon compounds.&#10;(iii) Xenon fluorides are excellent reducing agents.&#10;A) All three are correct.&#10;B) (i) and (ii)&#10;C) (ii) and (iii)

Accepted Answer

(i) Xenon fluorides can act as Lewis acids by accepting electron pairs. (ii) They are indeed used as starting materials for synthesizing other xenon compounds, showcasing their versatility in chemistry. (iii) is incorrect because xenon fluorides are generally good oxidizing agents, not reducing agents, due to their ability to accept electrons.

Question 6

Which of the following xenon oxides has not been identified? A) XeOS B) Xe₂O₃ C) XeO₄

Accepted Answer

It appears there is a formatting issue with the chemical formulas provided in the question. The "S1U1B1" sequences seem to be artifacts from a text encoding error. However, I will attempt to interpret the question as best as I can.
The question seems to be asking which of the following xenon oxides has not been identified:
a. XeO
b. XeO3
c. XeO4
Among these options:
a. XeO (xenon monoxide) has been studied under extreme conditions, but it is not a stable compound under normal conditions and is not well-characterized.
b. XeO3 (xenon trioxide) is a well-known compound that is stable at room temperature and has been extensively studied.
c. XeO4 (xenon tetroxide) is also a known compound, although it is highly unstable and can explode upon contact with organic materials.
Based on the information above, the xenon oxide that has not been identified as a stable and well-characterized compound under normal conditions is XeO (xenon monoxide). Therefore, the correct answer would be:
A: XeO (xenon monoxide) has not been identified as a stable compound under normal conditions.

Question 7

Which compounds are commonly used as a source of alkyl and/or aryl groups in the synthesis of organoxenon compounds?&#10;A) Organoboron and organosilicon compounds&#10;B) Grignard reagents&#10;C) Organolithium reagents.

Accepted Answer

Organoboron and organosilicon compounds are commonly used as a source of alkyl and/or aryl groups in the synthesis of organoxenon compounds because they are stable, easy to handle, and can be used to generate a variety of different alkyl and aryl groups.

Question 8

Xenon cannot serve as a ligand in coordination chemistry.&#10;A) This statement is correct.&#10;B) This statement is incorrect.&#10;C) It is correct only if Xe is bonded to another atom (such as F).

Accepted Answer

Xenon, being a noble gas, can indeed form compounds and act as a ligand in coordination chemistry, especially when it forms compounds like xenon hexafluoroplatinate (XePtF6), demonstrating its ability to participate in chemical bonding despite its inert nature.

Question 9

Radon has lower ionization energy than xenon, and we can expect it to be more reactive. Why is Rn chemistry less understood than xenon's?&#10;A) Rn is rare and radioactive.&#10;B) Radon compounds are not very useful.&#10;C) All available radon is used in industry rather than in laboratory.

Accepted Answer

Radon's rarity and radioactivity make it difficult to study extensively, as it poses safety risks and is less available for research compared to more stable and abundant elements like xenon.

Question 10

Compounds of xenon such as HXeCl have been identified. How can this and similar compounds be prepared?&#10;A) Starting from a xenon fluoride and another common reagent (such as HCl)&#10;B) The same method as for the synthesis of Xe fluorides: from the elements under high pressures and elevated temperatures.&#10;C) A starting reagent (i.e. HCl) is dispersed in a large volume of Xe matrix and exposed to light.

Accepted Answer

The answer of Compounds of xenon such as HXeCl have...

Deck 18: The Group 18 Elements