Question

which represents a decrease in entropy?
a) nacl dissolving in water
b) boiling water
c) condensation of steam on cold glass
d) sublimation of co₂

81 entropy is a measure of:
a) order
b) disorder

Explanation:

Entropy is a measure of disorder. A decrease in entropy means a change from a more disordered to a more ordered state. When steam (a gas) condenses on a cold glass to form liquid water, the molecules become more ordered as they go from a highly - dispersed gas state to a more closely - packed liquid state. Dissolving NaCl in water increases entropy as the ions disperse in the water. Boiling water and sublimation of CO₂ both increase entropy as they involve transitions to more disordered states (liquid to gas and solid to gas respectively). Entropy is defined as a measure of disorder.

Answer:

For the first question: c) condensation of steam on cold glass
For the second question: b) disorder