Final answer:
Approximately 25 grams of copper sulfite would dissolve at 70°C. So, the correct option would be (b).
Step-by-step explanation:
The solubility of copper sulfate in water at 70°C is influenced by factors such as temperature, pressure, and the presence of other solutes. At 70°C, the solubility of copper sulfate is relatively high compared to lower temperatures. The solubility of copper sulfate in water increases with temperature. At 70°C, more copper sulfate can dissolve compared to lower temperatures.
In this context, option (b) stating 25 grams would be correct. As the temperature rises, the kinetic energy of water molecules increases, allowing them to break the bonds holding the copper sulfate molecules together. This results in a higher solubility of copper sulfate in the solvent. However, it's crucial to note that the exact solubility depends on various factors such as the purity of the copper sulfate and the specific conditions of the solution. Therefore, while the general trend is that more copper sulfate dissolves at higher temperatures, the specific value can vary. Option (b) is a reasonable estimate based on the typical behavior of solutes like copper sulfate in aqueous solutions at elevated temperatures.