The soldiers of Napoleon's army while at Alps during freezing winter suffered a serious problem as regards to the tin buttons of their uniforms. White metallic tin buttons got converted to grey powder. This transformation is related to:
- Aan interaction with nitrogen of the air at very low temperatures
- Ban interaction with water vapour contained in the humid air
- Ca change in the partial pressure of oxygen in the air
- Da change in the crystalline structure of tin
Solution & Step-by-step Explanation
Tin exhibits allotropy. White tin ( -form, metallic) is stable at room temperature. Below , it slowly transforms into grey tin ( -form, non-metallic/powder), which has a diamond cubic crystalline structure. At freezing temperatures, this transformation happens, causing the buttons to disintegrate into powder.