Reactions with Noble Gases

F2 mixes homogeneously with equimolar amounts of Ar at 85 K or Kr at 120 K without reaction. It dissolves about 30 mol% of Kr at 77 K and forms two separate layers with Xe at 90 K [1]. 

No reaction is observed in equimolar mixtures of OFg and Kr [3] or Xe [2] in the dark at 25°C. Irradiation of the mixtures with sunlight gives the noble gas difluorides [2, 3]. 

Pressure measurements show that heating an equimolar mixture of OF2 and Xe above 560 K initiates a reaction (no further details) [4]. The reaction of OF2 with Xe in an electric discharge (195 K, 3 to 62 Torr) or in a nickel tube at about 400°C at a starting pressure of about 

5 atm yields Xep4 and xenon oxide fluorides [5]. Thus, xenon oxide fluorides are obtained from equal volumes of OF2 and Xe at 195 K and a maximum pressure of 60 Torr applying 1.2 to 

6 keV and 12 to 32 mA. Heating a 1 1 molar OF2-Xe mixture for 4.75 h at300°C in a nickel tube gives crystals of the empirical formula Xei 2O1.1F30 [6]. 

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Reactions with Elements 4.1.4.11.5.1 Reactions with Noble Gases... 

Reactions with Inorganic Compounds 4.1.4.11.6.1 Reactions with Noble Gas Compounds... 

In recent years, aqueous solutions of Xe03 have been used to oxidize a species in solution, from which A[H°m can be calculated when AH for the oxidation reaction is combined with AH for other reactions. The noble gas oxide Xe03 is used as an oxidant because of its stability and the fact that the final reaction product is Xe(g), which has a zero enthalpy of formation and is easily removed from the reaction mixture. As an example, O Hare4 has reported AfHcm for UCI4. We will not go through the details of his procedure, but the critical step involved measuring A TH for the reaction... 

Fluorofullerenes have been prepared by reaction with halogen fluorides, by direct fluorination with F2 or by fluorination with noble gas fluorides [7,8,14], The reaction with high valence metal fluorides is the most versatile route for the synthesis of CsoFnH. 

SiH3+ ions are easily formed in the reactions of noble gas cations and other small ions with SiFLt via dissociative charge transfer (equation l)11. 

Fig. 44 Observed thermal and photoinduced reactions of FSO2N3. Solid arrows indicate photo-induced reactions in noble gas cryomatrices dashed arrows indicate gas-phase reactions. Reprinted with permission X. Zeng, H. Beckers and H. Willner, J. Am. Chem. Soc., 2013, 135, 2096. Copyright (2013) American Chemical Society.

Older methods use a liquid phase process (Figure 10-11). ° New gas-phase processes operate at higher temperatures with noble metal catalysts. Using high temperatures accelerates the reaction (faster rate). The hydrogenation of benzene to cyclohexane is characterized by a highly exothermic reaction and a significant decrease in the product volume... 

A radical is highly reactive because it contains an atom with an odd number of electrons (usually seven) in its valence shell, rather than a stable, noble-gas octet. A radical can achieve a valencC Shel octet in several wavs, for example, the radical might abstract an atom and one bonding electron from another reactant, leaving behind a new radical. The net result is a radical substitution reaction ... 

The solutions of mer-OsCl3(PR3)3 undergo an interesting reduction with zinc amalgam [155] to form OsCl2(PR3)2L (Figure 1.62), where L is a molecule abstracted from the atmosphere in the reaction flask if a noble gas, incapable of coordination, is employed, coordinative saturation is obtained by dimerization to [(PR3)3OsCl3Os(PR3)3]+. 

At least since the mid-19th century, it has never been claimed that molecular nitrogen is completely unreactive with organic reagents. It was, however, known that many reactions that cannot be carried out in air because of reactions with oxygen, can be performed in a so-called inert atmosphere consisting of either a noble gas or — more cheaply — N2. This is common knowledge to the experimental chemist. 

CO oxidation, an important step in automotive exhaust catalysis, is relatively simple and has been the subject of numerous fundamental studies. The reaction is catalyzed by noble metals such as platinum, palladium, rhodium, iridium, and even by gold, provided the gold particles are very small. We will assume that the oxidation on such catalysts proceeds through a mechanism in which adsorbed CO, O and CO2 are equilibrated with the gas phase, i.e. that we can use the quasi-equilibrium approximation. 

Phenylisosilacyanide is produced either by irradiation of triazidophenyl-silane in matrix isolation or by pyrolysis followed by trapping in noble gas matrix (Eq. 3). The reaction with /-butanol leads to the expected product6 ... 

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