Which color describes the solid form of iodine?

Which color describes the solid form of iodine?

• A. Grey
• B. Purple
• C. Black
• D. Orange

Answer: (A)

In a substance, color can change with state. Iodine behaves differently as a solid than as a gas. When iodine is solid, it forms grey crystalline chunks that have a dull, metallic-like appearance. The vivid purple color people associate with iodine comes from its vapour, not the solid. So the solid is described as grey, while the purple is seen in the sublimed gas. The orange and black options don’t match the typical solid appearance, and while very dark solids can look almost black, the standard description for solid iodine is grey.

In a substance, color can change with state. Iodine behaves differently as a solid than as a gas. When iodine is solid, it forms grey crystalline chunks that have a dull, metallic-like appearance. The vivid purple color people associate with iodine comes from its vapour, not the solid. So the solid is described as grey, while the purple is seen in the sublimed gas. The orange and black options don’t match the typical solid appearance, and while very dark solids can look almost black, the standard description for solid iodine is grey.