The color of iodine solution is typically a deep brown color, often described as dark amber. When iodine is dissolved in water, it forms a solution that can appear yellowish, but the common laboratory iodine tincture – a mixture of iodine and alcohol – is recognizable for its dark hue.
This distinctive color is due to the iodine molecules absorbing certain wavelengths of light. The presence of iodine in solution can also lead to a more vivid blue-black color when it complexes with starch, making it an important indicator in many chemical tests.