As each electron is removed, one at a time, from an atom of aluminum, more ionization energy is requiredBetween which two successive ionization energies would you expect the greatest difference (largest change in value)? Explain your answer in terms of attraction, repulsion, and electron arrangement.
Generally steel is to heavy for aviation use but specialist steels are still used in a few high stress areas, mostly within the engines or the undercarriageThere have been the odd exception thoughBack in the early 1960s the British built the Bristol type 188 which was mostly stainless steelIt was designed to fly continuously above Mach 1 and it was ahead of it's timeBasically it was a research tool and only 2 ever flewA third was built for ground testingThe prototype survives and can be seen at the aviation museum at RAF Cosford in South WalesThere are photographs of it on Wikipedia, just search Bristol 188 to find it Ian M
Some MiG 25s, like the one that defected to Taiwan, had a lot more mild steel in their construction than anyone expectedBut in general there's very little steel in planes, the strength to weight ratio is just too badPlaces where you might think they'd use a small amount of steel for strength and heat resistance they mostly use titaniumThe majority of contemporary airframes are aluminum alloy and more modern aircraft are substituting compositesIf I had to get steel out of a plane I'd look at cylinder liners, cranks and valvetrain components in piston aircraft and turbine shafts in jets.
Back in the day, a number of amphibians were made out of stainless steel to minimize corrosionthe construction was usually spot welded, but the combination of the weight of the steel and its brittleness creating cracks kept it from being a common practice.
The first ionization energy of Al would result in Al+, similar to that of Mg structureThe second ionization energy of Al would result in Al2+, similar to that of Na structureThe third ionization energy of Al would result in Al3+, similar to that of Neon structureBy this time, there is a stronger nuclear attraction because there is a lot less electrons in the electron cloud (and a higher proton to electron ratio)There is also less electrons, thus having less electron-to-electron repulsions The fourth ionization energy of Al would result in Al4+, similar to that of F structureBut at this point, you are taking electrons from a more stable energy levelAs such, to take electrons from a very stable level requires a lot more energyThus, the fourth ionization energy of Al should be the greatest one.
