Final answer:
The pipe to transport hot alkaline water is designed for c) Corrosive Fluids because hot alkaline water can be highly corrosive, leading to issues like boiler scale, which is less about pressure and more about the corrosive chemical reactions involving bicarbonate ions and calcium carbonate.
Step-by-step explanation:
A pipe designed to transport hot alkaline water must be capable of handling the unique properties associated with high temperatures and basic (alkaline) fluids. Among the options provided, the correct answer to what the pipe is designed for is c) Corrosive Fluids. This is because alkaline water, especially when hot, can be highly corrosive to many materials. Hot water can speed up the chemical reaction rates that lead to corrosion, and the alkalinity can precipitate a process similar to what is observed with boiler scale. The chemistry behind boiler scale involves the reaction of bicarbonate ions converting to calcium carbonate, which is much less soluble and can deposit on the pipe walls, impeding water flow and heat transfer.
As for the pressure, hot water plumbing systems can be under various pressures depending upon their specific use and design specifications. Therefore, the design for 'high pressure' or 'low pressure' would depend on the application and cannot be determined from the information given. The mention of 'gaseous substances' is not directly relevant, although it is true that the solubility of gases in water changes with temperature and pressure, affecting the potential for gaseous corrosion in some circumstances.