Question

1. Положите в пробирку три-четыре кристалла йода, залейте сверху 1—2 мл воды и перемешайте. Понаблюдайте процесс растворения Йода в воде. Затем к водному раствору йода добавьте 1-2 мл бензола и взболтайте пробирку. Дайте отстояться. Понаблюдайте за происходящими изменениями. Обратите внимание на окраску образовавшихся в пробирке двух слоев: водного и бензольного. 2. Выскажите свое мнение о растворимости йода в воде и органическом растворителе бензоле.

Answer 1

Ответ:

Йод малорастворим в воде, насыщенный р-р содержит всего 0,03% Йода. В бензоле растворимость йода гораздо выше. В отношении растворимости есть правило - подобное растворяется в подобном. Молекула иода имеет ковалентную неполярную связь, а бензол неполярный растворитель ( в отличие от воды).

Answer 2

Solubility of Iodine in Water and Benzene

When iodine crystals are added to a test tube containing water and then mixed, the iodine dissolves in the water. After that, when benzene is added to the iodine-water solution and the test tube is shaken, two distinct layers are formed: a water layer and a benzene layer. The color of each layer may vary.

The solubility of iodine in water is relatively high. Iodine is a nonpolar molecule, and water is a polar solvent. However, iodine can dissolve in water due to the formation of temporary induced dipoles in the iodine molecule. This allows iodine to interact with the polar water molecules through weak intermolecular forces, such as dipole-dipole interactions and London dispersion forces. The resulting solution is typically brown in color due to the presence of iodine ions (I3-) formed by the reaction of iodine with water.

On the other hand, benzene is an organic solvent that is nonpolar. Iodine is also nonpolar, so it can dissolve in benzene as well. The solubility of iodine in benzene is relatively low compared to its solubility in water. The resulting solution is typically purple in color due to the presence of undissociated iodine molecules.

In summary, iodine is soluble in both water and benzene, but the solubility is higher in water due to the polar nature of water molecules. The solubility of iodine in benzene is lower because benzene is a nonpolar solvent.