Which mathematical expression defines the standard entropy change,

CHEMISTRY · Single correct · A Level · Chemistry · Thermodynamics · Thermodynamics

Problem

\Delta S^\circ_{\text{rxn}}

, for a chemical reaction written as

a\,A + b\,B \rightarrow c\,C + d\,D

? (a)

\displaystyle \frac{c\,S^\circ_{C} + d\,S^\circ_{D}}{a\,S^\circ_{A} + b\,S^\circ_{B}}

(b)

c\,S^\circ_{C} + d\,S^\circ_{D} + a\,S^\circ_{A} + b\,S^\circ_{B}

(c)

c\,S^\circ_{C} + d\,S^\circ_{D} - \left(a\,S^\circ_{A} + b\,S^\circ_{B}\right)

(d)

a\,S^\circ_{A} + b\,S^\circ_{B} - \left(c\,S^\circ_{C} + d\,S^\circ_{D}\right)