The equilibrium reaction below has the kc = 0.254 at 25°c. if the temperature of the system at equilibrium is decreased to 0°c, how and for what reason will the equilibrium shift? also show and explain how and why the kc value will change.

The equilibrium shifts towards reagents

Explanation:

Is known  rised to the power of their number of moles in the balanced reaction. When you have a system at equilibrium with Kc < 1, it means [products] < [reagents] and the system needs energy to react, so if you decrease tempeture the equilibrium shifts towards reagents and less products will be created.

This efect can be discribed with Van´t Hoff equation: where we can see that if we decrease temperature (this is T2<T1) in consecuense K2<K1 and reaction doesn´t happen.

atomic mass = 39

number of neutrons = 20

number of protons= 19

electronic configuration = 1s2 2s2 2p6 3s2 3p6 4s1

the number of electron in first shell = 2

number of electrons in n=3 shell = 8