Question

ПОМОГИТЕ ПОЖАЛУЙСТА. Очень нужно!!!! ДАЮ 50 баллов!! 1)Распределите данные вещества на 2 группы и объясните ваш выбор:а) H2O; S8; Cl2; HFб) NH3; HВr ; He; H2в) N2; O3; HI; H2O2г) O2; HCl; I2; H2S2) Напишите схему образования ковалентной связи в молекуле LiF

Answer 1

Ответ:

Н20 S8 C12 HE

02 HCI 12 HAS

Answer 2

#### Grouping Substances and Explaining the Choice To group the given substances into two groups, we need to consider their chemical properties and characteristics. Based on these factors, we can categorize the substances as follows: a) **H2O**, **S8**, **Cl2**, **HF**: These substances are all molecular compounds. H2O is a polar molecule due to the electronegativity difference between hydrogen and oxygen atoms. S8 and Cl2 are nonpolar molecules because the atoms in these molecules have similar electronegativities. HF is a polar molecule due to the electronegativity difference between hydrogen and fluorine atoms. Therefore, we can group these substances together as molecular compounds. b) **NH3**, **HBr**, **He**, **H2**: NH3 is a polar molecule due to the electronegativity difference between nitrogen and hydrogen atoms. HBr is also a polar molecule due to the electronegativity difference between hydrogen and bromine atoms. He is a noble gas and exists as individual atoms. H2 is a diatomic molecule with nonpolar covalent bonds. Therefore, we can group these substances together as a combination of polar and nonpolar molecules. c) **N2**, **O3**, **HI**, **H2O2**: N2 is a nonpolar molecule due to the similar electronegativities of nitrogen atoms. O3 is a polar molecule due to the presence of a bent molecular geometry and the electronegativity difference between oxygen atoms. HI is a polar molecule due to the electronegativity difference between hydrogen and iodine atoms. H2O2 is a polar molecule due to the electronegativity difference between hydrogen and oxygen atoms. Therefore, we can group these substances together as a combination of polar and nonpolar molecules. d) **O2**, **HCl**, **I2**, **H2S**: O2 is a nonpolar molecule due to the similar electronegativities of oxygen atoms. HCl is a polar molecule due to the electronegativity difference between hydrogen and chlorine atoms. I2 is a nonpolar molecule due to the similar electronegativities of iodine atoms. H2S is a polar molecule due to the electronegativity difference between hydrogen and sulfur atoms. Therefore, we can group these substances together as a combination of polar and nonpolar molecules. #### Formation of Covalent Bond in LiF The formation of a covalent bond in the molecule LiF involves the sharing of electrons between the lithium (Li) and fluorine (F) atoms. Here is a simplified diagram illustrating the formation of a covalent bond in LiF: 1. The lithium atom has one valence electron in its outermost shell, while the fluorine atom has seven valence electrons. 2. The lithium atom donates its valence electron to the fluorine atom, resulting in the formation of a positively charged lithium ion (Li+) and a negatively charged fluorine ion (F-). 3. The lithium ion and fluorine ion are attracted to each other due to their opposite charges. 4. The lithium ion and fluorine ion come close together, and the electron donated by lithium is shared between the two atoms. 5. This shared pair of electrons forms a covalent bond between the lithium and fluorine atoms. 6. The resulting molecule is LiF, where the lithium atom is surrounded by a full outer shell of electrons from the shared pair, and the fluorine atom also has a full outer shell. The formation of a covalent bond in LiF allows both the lithium and fluorine atoms to achieve a stable electron configuration, following the octet rule.