Question

Попробуйте объяснить почему простые вещества галогены в обычных условиях находятся в различных агрегатных состояниях: F2 и хлор Cl2 -газы, бром Br2 -жидкость, иод I2 -ккристаллическое вещество. (F2=F и F это пояснение "2") Помогите пожалуйста!

Answer 1

Потому что с ростом молекулярной массы молекулы теряют свою подвижность, становятся более инертными и слабых межмолекулярных электростатических взаимодействий становится достаточно для того, чтобы удерживать молекулы вместе. Поэтому, хлор и фтор газы, бром-жидкость, йод - твердое вещество.

Answer 2

Explanation of Different States of Halogens

In ordinary conditions, halogens exist in different states of matter. Fluorine (F2) and chlorine (Cl2) are gases, bromine (Br2) is a liquid, and iodine (I2) is a crystalline solid. This variation in states can be explained by the intermolecular forces and the strength of the bonds between the halogen atoms.

1. Fluorine (F2) and Chlorine (Cl2): Gases Fluorine and chlorine are both gases at room temperature and atmospheric pressure. This is because the intermolecular forces between the halogen molecules are relatively weak. The halogen molecules are held together by covalent bonds, which are formed by the sharing of electrons between the atoms. In the case of fluorine and chlorine, each halogen atom forms a single covalent bond with another halogen atom, resulting in a diatomic molecule (F2 or Cl2).

The weak intermolecular forces between the diatomic molecules of fluorine and chlorine allow them to easily overcome these forces and exist as gases. The low boiling points of fluorine (-188.1°C) and chlorine (-34.04°C) further support their gaseous state at room temperature [[1]].

2. Bromine (Br2): Liquid Bromine is a liquid at room temperature and atmospheric pressure. Unlike fluorine and chlorine, bromine molecules are larger and have stronger intermolecular forces. The bromine molecule (Br2) consists of two bromine atoms held together by a covalent bond.

The larger size of bromine atoms and the presence of more electrons result in stronger London dispersion forces between the bromine molecules. These forces are a type of intermolecular force that arises due to temporary fluctuations in electron distribution, creating temporary dipoles. The stronger intermolecular forces in bromine require more energy to break, resulting in a higher boiling point of bromine (58.8°C) compared to fluorine and chlorine [[2]].

3. Iodine (I2): Crystalline Solid Iodine is a crystalline solid at room temperature and atmospheric pressure. Iodine molecules (I2) are larger and heavier than those of fluorine, chlorine, and bromine. The intermolecular forces in iodine are even stronger than in bromine due to the larger size and greater number of electrons.

The strong intermolecular forces in iodine are primarily due to London dispersion forces. These forces become even stronger as the size and number of electrons in the molecules increase. The high boiling point of iodine (184.3°C) is a result of the significant energy required to overcome these strong intermolecular forces and transition from a solid to a liquid or gas [[3]].

Conclusion

In summary, the different states of halogens in ordinary conditions can be attributed to the strength of the intermolecular forces between the halogen molecules. Fluorine and chlorine are gases due to their weak intermolecular forces, bromine is a liquid due to stronger intermolecular forces, and iodine is a crystalline solid due to even stronger intermolecular forces.