Alpha tin is the same as gray tin.

Alpha tin is the same as gray tin.

• A. Alpha tin is the same as gray tin.
• B. Alpha tin is the same as white tin.
• C. Alpha tin is a liquid form.
• D. Alpha tin is a salt.

Answer: (A)

Tin has two solid forms that differ in structure, a phenomenon called allotropy. The form known as alpha tin is the same as gray tin. It has a diamond-like crystal structure and, at temperatures below about 13.2°C, exists as a gray, brittle solid. When tin is warmed past that transition temperature, it tends to change into the other form, beta tin (white tin), which is metallic and shiny. So the statement that alpha tin is gray tin aligns with this naming: alpha equals gray, both describing the same low-temperature, nonmetallic allotrope. The other descriptions don’t fit because white tin is the metallic form (beta tin), not alpha; there isn’t a separate liquid form for these solid allotropes under normal conditions; and tin in this context isn’t a salt.

Tin has two solid forms that differ in structure, a phenomenon called allotropy. The form known as alpha tin is the same as gray tin. It has a diamond-like crystal structure and, at temperatures below about 13.2°C, exists as a gray, brittle solid. When tin is warmed past that transition temperature, it tends to change into the other form, beta tin (white tin), which is metallic and shiny. So the statement that alpha tin is gray tin aligns with this naming: alpha equals gray, both describing the same low-temperature, nonmetallic allotrope.

The other descriptions don’t fit because white tin is the metallic form (beta tin), not alpha; there isn’t a separate liquid form for these solid allotropes under normal conditions; and tin in this context isn’t a salt.