Which of the following is a chemical change? a. a solution of salt water being diluted as water is added to it b. a rock eroding as the wind removes particles from it c. soil drying as water evaporates d. silver tarnishing as the silver metal reacts with sulfur

Silver tarnishing as the silver metal reacts with sulphur is a chemical change.

Explanation:

Tarnishing is the process of chemical change occurring on the surface of objects leading to corrosion or other defects on the surface. The remaining options like dilution, eroding is a physical change where the concentration of salt and rock particles will be decreased, respectively.

Similarly for soil drying also the concentration of water will be decreased leading to a physical change from wetty or dry soil.

But the last option which indicates tarnishing of silver metal on reaction with sulphur is a chemical process as the surface of silver metal will be reacting to sulphur and leads to lose of electrons which leads to corrosion of the surface or tarnishing of silver.