Explanation:
Medicinal chemistry and pharmaceutical chemistry are disciplines at the intersection ofchemistry, especially synthetic organicchemistry, and pharmacology and various other biological specialties, where they are involved with design,chemical synthesis and development for market of pharmaceutical agents, or bio-active ...
Let the solution cool down really slowly, don’t disturb it at all.
Lol it literally says that he covered the distance in three seconds so I believe it would be three
Here we have to get the 
of the reaction at 520 K temperature.
The of the reaction is 1.705 atm
We know the relation between and 
is 
, where = The equilibrium constant of the reaction in terms of partial pressure, = The equilibrium constant of the reaction in terms of concentration and N = number of moles of gaseous products - Number of moles of gaseous reactants.
Now in this reaction, PCl₃ + Cl₂ ⇄ PCl₅
Thus number of moles of gaseous product is 1, and number of moles of gaseous reactants are 2. Thus N = |1 - 2| = 1 mole
The given value of is 4.0×10⁻²
The molar gas constant, R = 0.082 L. Atm. mol⁻¹. K⁻¹ and temperature, T = 520 K.
On plugging the values in the equation we get,
Or, = 1.705 atm
Thus, the of the reaction is 1.705 atm
