An industrial chemical plant is designing a replacement injection nozzle for a high-temperature sulfuric acid gas-processing reactor. Inside the reactor, the gaseous environment reaches temperatures of up to 450 ∘C450\ ^\circ\text{C}450 ∘C and contains highly corrosive, concentrated sulfuric acid vapor (H2SO4\text{H}_2\text{SO}_4H2SO4). To prevent mechanical strain on the reactor's high-speed rotating assembly, the total weight of the nozzle must be kept as low as possible. The nozzle must also withstand the elevated temperatures and corrosive acidic atmosphere.
The table below outlines the physical and chemical properties of several metals that could be utilized to fabricate the nozzle:
MetalMelting point (∘C)Relative densityReaction with sulfuric acidIron15387.9reacts rapidlyLead32711.3reacts slowlyMagnesium6501.7reacts violentlySilver96210.5no reactionTitanium16684.5no reactionZinc4207.1reacts vigorously \begin{array}{|l|c|c|l|} \hline \textbf{Metal} & \textbf{Melting point } (^\circ\text{C}) & \textbf{Relative density} & \textbf{Reaction with sulfuric acid} \\ \hline \text{Iron} & 1538 & 7.9 & \text{reacts rapidly} \\ \hline \text{Lead} & 327 & 11.3 & \text{reacts slowly} \\ \hline \text{Magnesium} & 650 & 1.7 & \text{reacts violently} \\ \hline \text{Silver} & 962 & 10.5 & \text{no reaction} \\ \hline \text{Titanium} & 1668 & 4.5 & \text{no reaction} \\ \hline \text{Zinc} & 420 & 7.1 & \text{reacts vigorously} \\ \hline \end{array} MetalIronLeadMagnesiumSilverTitaniumZincMelting point (∘C)15383276509621668420Relative density7.911.31.710.54.57.1Reaction with sulfuric acidreacts rapidlyreacts slowlyreacts violentlyno reactionno reactionreacts vigorouslyUse the information in the table to answer the following questions:
Which metal in the table could be used to make a nozzle with the lowest density?
Why would this metal be unsuitable for the nozzle's outer structure?
Lead is commonly used in heavy-duty industrial gaskets. Why would lead not be suitable for use in the structural joints of this nozzle?
Choose a metal from the table that would be the most suitable for making the structural body of the nozzle. Give two reasons for your choice.
34 exam-style questions on Edexcel IGCSE Chemistry Reactivity series. Each one has a worked solution and a mark scheme showing where the marks go.