Final Answer:
Solubility in water is a chemical property. Option 4 is answer.
Step-by-step explanation:
Solubility in water refers to the ability of a substance to dissolve in water, and this is a characteristic feature associated with the chemical nature of the substance. Chemical properties are inherent to the composition and behavior of substances at the molecular level. In the case of solubility, it involves the interaction between the solute and solvent molecules, leading to the formation of a homogeneous solution. This phenomenon is specific to the chemical makeup of the substances involved. In contrast, physical properties, biochemical properties, and kinetic properties are more related to the observable characteristics, processes, or behaviors at macroscopic or microscopic levels.
Therefore, the answer is 4) chemical property.