Final answer:
If gaseous oxygen and dissolved oxygen have the same partial pressure, they will diffuse into solid materials at the same rate.
Step-by-step explanation:
According to Henry's law, the concentration of a dissolved gas in a liquid is directly proportional to its partial pressure. This means that if gaseous oxygen and dissolved oxygen in water have the same partial pressure, they will have the same concentration in the water.
Therefore, if the gaseous oxygen and dissolved oxygen have the same partial pressure, they will diffuse into solid materials at the same rate.