Pcl5 => pcl3+cl2
the no of moles of cl2 produced will be if one mole of pcl5 is heated 250c in vessel having a capacity of 10dm^3. at 250°c kc= 0.041

0.47 moles

Explanation:

Initial moles of   = 1 mole

Volume of container =

Initial concentration of  

The given balanced equilibrium reaction is,

Initial conc.         0.1 M             0    0

At eqm. conc.    (0.1-x) M   (x) M   (x) M

The expression for equilibrium constant for this reaction will be,

Solving for x:

Thus concentration of produced is 0.047 M

where,

n= moles of solute  

= volume of solution in L

Thus moles of produced is 0.47.

the seeing the electronic configuration we can say that the element is fluorine.

fluorine is the most electronegative element in the periodic table.

but by only seeing the configuration we cannot say about its reactivity because we don't know if its configuration after excitation or by addition of electrons.

but if not then, it is the lightest halogen and exists as a highly toxic pale yellow diatomic gas at standard conditions. as the most electronegative element, it is extremely reactive: almost all other elements, including some noble gases, form compounds with fluorine.