Answer:
Noble gases are considered as Inert because they are unreactive.
Explanation:
Seven noble elments are known to us , they are: helium, neon, argon, krypton, xenon, radon, and oganesson. Noble gases have 8 electrons in their outermost shell and hence their valence shell is complete, they donot need further electrons to complete their octet so they are unreactive. Also they posses following properties.
Burning wood
dissolving salt in water
<span>mixing acid and base</span>
The reaction described above is a series of sn2 substitutions. The initial (<em>R</em>)-2-butanol reacts with PBr₃ in pyridine to turn the alcohol functionality into a leaving group as it attaches to the phosphorus of PBr₃. One of the bromides from PBr₃ eventually displaces the oxygen atom with an sn2 substitution. Therefore, the product will have an inversion of stereochemistry as (<em>S</em>)-2-bromobutane is formed.
This product is treated with NaCN and CN⁻ is a very good nucleophile. The bromo-substitutent is a good leaving group, therefore, the nucleophile will do an sn2 substitution which inverts the stereochemistry once more to give the optically active product shown.
This is what I found. Hope this helps:)