Predict in which of the following entropy increases. (a) A liquid crystallizes into a solid (b) Temperature of a crystalline solid is raised from 0 K to 115 K (c) (2 NaHCO ₃( ~s ) Na ₂ CO ₃( ~s )+ CO ₂( ~g )+ H ₂ O ( g ) ) (d) ( H ₂( ~g ) 2 H ( g ) ) The correct one is -

Step-by-step solution

- (a) A liquid crystallizes into a solid: Entropy decreases as the system becomes more ordered. - (b) Temperature of a crystalline solid is raised from ( 0 ~ K ) to ( 1 1 5 ~ K ) : Entropy increases because increasing temperature increases molecular motion and disorder. (c) (2 NaHCO 3( ~s ) Na 2 CO 3( ~s )+ CO 2( ~g )+ H 2 O ( g ) ) : Entropy increases because gases (CO2 and H2O) are produced, leading to more disorder. - (d) ( H 2 (g) 2 H (g) ) : Entropy increases as one molecule of H2 breaks into two atoms, increa