Suppose you have a supply of the following metals: Fe, Ni,Sc, Cr, Au, K. Which of there could be mixed to make substitutional alloys? Which metals are incompatible for this purpose. Clearly explain why there metals would be incompatible.
I am unsure about the metals that are incompatible. I think the metals that answer this part are K and Sc because they are so far away on the periodic table from the other elements that all have similar sizes. Help?!
To determine which metals can be mixed to make substitutional alloys, we need to consider their atomic sizes and electronegativities.
Substitutional alloys are formed when atoms of one metal are substituted with atoms of another metal within the crystal lattice. For successful substitutional alloy formation, the metals should have similar atomic sizes and electronegativities.
Let's analyze the given metals for their compatibility:
1. Fe (Iron): Iron is compatible for substitutional alloys with most of the metals because it has a moderate atomic size and electronegativity.
2. Ni (Nickel): Nickel is compatible with many other metals for substitutional alloys. It has a similar atomic size and electronegativity to metals such as Fe, Co, and Cu.
3. Sc (Scandium): Scandium is not compatible for substitutional alloys with the other given metals because it has a significantly smaller atomic size compared to them. Being much smaller can lead to disruption of the crystal lattice, resulting in limited solid solubility and poor mechanical properties. Therefore, Scandium is incompatible for this purpose.
4. Cr (Chromium): Chromium is compatible for substitutional alloys with metals like Fe, Ni, and Co due to its similar atomic size and electronegativity.
5. Au (Gold): Gold is compatible for substitutional alloys with some other metals, especially those in its vicinity in the periodic table, such as Cu, Pt, and Ag.
6. K (Potassium): Potassium is incompatible for substitutional alloys with the other given metals because it has a significantly larger atomic size compared to them. This substantial difference in atomic size would lead to lattice distortion and hinder the formation of substitutional alloys.
To summarize, the metals that could potentially be mixed to make substitutional alloys are Fe, Ni, Cr, and Au, while Sc and K are incompatible due to their significant differences in atomic size compared to the other metals.
To determine which metals can be mixed to make substitutional alloys, we need to consider the principle of solid solubility. According to this principle, two metals can form a solid solution if their atomic sizes are similar and have comparable electronegativities.
In this case, we have the following metals: Fe, Ni, Sc, Cr, Au, and K. Let's analyze them one by one.
1. Fe (Iron): Iron is commonly used in substitutional alloys, such as stainless steel, due to its ability to form solid solutions with many other metals.
2. Ni (Nickel): Nickel is highly compatible with iron, and the two metals can form a complete solid solution over a wide range of compositions.
3. Sc (Scandium): Scandium is not commonly used in substitutional alloys. It has a significantly smaller atomic size compared to the other metals in the list, which makes it challenging to mix with them to form a solid solution.
4. Cr (Chromium): Chromium forms solid solutions with iron and nickel, which are commonly used in various alloy applications.
5. Au (Gold): Gold is not typically used in substitutional alloys because it has a significantly larger atomic size compared to iron and nickel.
6. K (Potassium): Potassium is highly incompatible with the other metals on the list. It has a significantly larger atomic size and a much lower electronegativity compared to the transition metals, making it difficult to form a solid solution.
Therefore, based on atomic size and electronegativity considerations, the metals that could be mixed to make substitutional alloys are Fe, Ni, Cr, and Sc, while Au and K would be incompatible for this purpose due to their atomic size differences and electronegativity disparities.