The change in entropy is related to the change in the number of moles of gas molecules. Determine the change in moles of gas for each of the reactions and decide if the entropy increases decreases or has little to no change.

The given question is incomplete. The complete question is:

The change in entropy is related to the change in the number of moles of gas molecules. Determine the change in moles of gas for each of the reactions and decide if the entropy increases decreases or has little to no change:

A.

B.

C.

D.

A. : decreases

B. : decreases

C. : no change

D. : increases

Explanation:

Entropy is defined as the randomness of the system.

Entropy is said to increase when the randomness of the system increase, is said to decrease when the randomness of the system decrease and is said to have no change when the randomness remains same.

In reaction , as gaseous reactant is changed to solid product, entropy decreases.

In reaction , as 4 moles of gaseous reactants is changed to 2 moles of gaseous product, entropy decreases.

In reaction , as 3 moles of gaseous reactants is changed to 3 moles of gaseous product, entropy has no change.

In reaction   , as 1 mole of gaseous reactant is changed to 3 moles of gaseous product, entropy increases.

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.