Pcl5 connection. Test in chemistry (grade 8) "Structure of the atom

“Basic types of chemical bonds” - Metallic bond. Mechanisms of covalent bond cleavage. Electrons. Na+Cl. Ionic chemical bond. Chemical bond. Communication polarity. Covalent bond parameters. Saturability. Hydrogen bond. Mechanisms of covalent bond formation. Properties of covalent bonds. Types of covalent bonds. Interaction of atoms in chemical compounds.

"Hydrogen bond" - Hydrogen bond. 2) between ammonia molecules. Subject. High temperatures. Occurs between molecules. Factors that destroy hydrogen bonds in a protein molecule (denaturing factors). 2) some alcohols and acids are unlimitedly soluble in water. 1) between water molecules. Electromagnetic radiation. Intramolecular hydrogen bond.

“Metallic chemical bond” - A metallic bond has features similar to a covalent bond. Metal chemical bond. The most ductile are gold, copper, and silver. The best conductors are copper and silver. Differences between metallic bonds and ionic and covalent bonds. A metallic bond is a chemical bond caused by the presence of relatively free electrons.

“Chemistry “Chemical Bond”” - Substances with covalent bonds. Covalent bond parameters. Covalent bond. Ionic bonding is an electrostatic attraction between ions. Metals form metallic crystal lattices. The number of shared electron pairs is equal to the number of bonds between two atoms. Hydrogen chemical bond. Species chemical bond and types of crystal lattices.

“Covalent bond” - Methods of bond formation. A 3. Chemical bond. In the sulfur (IV) oxide molecule there are bonds 1) 1b and 1 P 2) 3b and 1 P 3) 4b 4) 2b and 2 P. Oxidation state and valence of chemical elements. The oxidation state is zero in the compounds: 1) Ca3P2 2) O3 3) P4O6 4) CaO 12. The highest oxidation state is shown in the compound 1) SO3 2) Al2S3 3) H2S 4) NaHSO3 11.

“Chemical bond and its types” - Polar bond. Interaction between atoms. Definition of the concept. Test work. Types of chemical bonds in inorganic substances. Covalent nonpolar bond. Characteristics of communication types. A winning path. Complete the task. Ionic bond. Communication characteristics parameters. Independent work.

There are a total of 23 presentations in the topic

61. What chemical bond is called a hydrogen bond? Give three examples of compounds with hydrogen bonding. Draw structural diagrams of the above associates. How does the formation of a hydrogen bond affect the properties of substances (viscosity, boiling and melting points, heat of fusion and vaporization?

62. Which bond is called an s-bond and which is called a p-bond? Which one is less durable? Depict structural formulas ethane C 2 H 6, ethylene C 2 H 4 and acetylene C 2 H 2. Label the s- and p-bonds on hydrocarbon structural diagrams.

63. In the molecules F 2, O 2, H 2 SO 4, HCl, CO 2, indicate the type of bonds, the number of s- and p-bonds.

64. What forces of intermolecular interaction are called dipole-dipole (orientational), inductive and dispersive? Explain the nature of these forces. What is the nature of the predominant intermolecular interaction forces in each of the following substances: H 2 O, HBr, Ar, N 2, NH 3?

65. Give two schemes for filling MOs during the formation of a donor-acceptor bond in systems with atomic populations:

a) electron pair – free orbital (2+0) and

b) electron pair – electron (2+1).

Determine the bond order, compare bond energies. Which of the considered bonds is involved in the formation of the ammonium ion +?

66. Based on the structure of atoms in normal and excited states, determine the covalency of beryllium and carbon in the molecules BeCl 2, (BeCl 2) n, CO and CO 2. Draw the structural formulas of the molecules.

67. Based on the provisions of the band theory of crystals, characterize metals, conductors and dielectrics. What determines the band gap? What impurities need to be added to silicon to turn it into:

a) n-semiconductor; b) p-semiconductor?

68. Give the electronic configuration of the NO molecule using the MO method. How do the magnetic properties and bond strength change during the transition from the NO molecule to the NO + molecular ion?

69. What chemical bond is called ionic? What is the mechanism of its formation? What properties of an ionic bond distinguish it from a covalent bond? Give examples of molecules with typically ionic bonds and indicate the type of crystal lattice. Compose the isoelectronic series of xenon.

70. Based on the structure of atoms in normal and excited states, determine the covalency of lithium and boron in the compounds: Li 2 Cl 2, LiF, -, BF 3.

71. Which chemical bond is called coordination or donor-acceptor? Disassemble the structure of complex 2+. Specify donor and acceptor. How does the valence bond (BC) method explain the tetrahedral structure of this ion?

72. Why does the PCl 5 molecule exist, but not the NCl 5 molecule, although nitrogen and phosphorus are in the same subgroup VA of the periodic table? What type of bond is between phosphorus and chlorine atoms? Indicate the type of hybridization of the phosphorus atom in the PCl 5 molecule.

73 Describe the types of crystal structures by the nature of the particles of lattice sites. What crystal structures do they have: CO 2, CH 3 COOH, diamond, graphite, NaCl, Zn? Arrange them in order of increasing energies of the crystal lattices. What is intercalation?

74. Give four examples of molecules and ions with delocalized bonds. Draw their structural formulas.

75. What type of hybridization is in the molecules CCl 4, H 2 O, NH 3? Draw diagrams of the relative positions of the hybrid clouds and indicate the angles between them.

76. Give two schemes for filling MOs during the interaction of two AOs with populations:

a) electron + electron (1+1) and

b) electron + vacant orbital (1+0).

Determine the covalency of each atom and the bond order. What are the limits of binding energy? Which of the following bonds are in the hydrogen molecule H 2 and the molecular ion?

77. Give the electronic configuration of the nitrogen molecule using the MO method. Prove why the nitrogen molecule has high dissociation energy.

78. What is dipole moment? How does it change in a series of similarly constructed molecules: HCl, HBr, HJ? What type of bond occurs between the hydrogen, chlorine, bromine and iodine atoms in the given molecules? s- or p-bonds in these molecules?

79. What is valence orbital hybridization? What structure do AB n type molecules have if the bond in them is formed due to sp-, sp 2 -, sp 3 - hybridization of the orbitals of the A atom? Give examples of molecules with the indicated types of hybridization. Specify the angles between the bonds.

80. Given pairs of substances: a) H 2 O and CO; b) Br 2 and CH 4; c) CaO and N 2; d) H 2 and NH 3. Which pair of substances is characterized by a covalent nonpolar bond? Draw structural diagrams of the selected molecules, indicate the shapes of these molecules and the angles between the bonds.

Option 1

2) indicate the period number and group number in the Periodic Table of Chemical Elements D.I. Mendeleev, in which this element is located;

Indicate the position of sulfur in the Periodic Table. Give its electronic formula.

Select from the list substances whose molecules contain a covalent nonpolar bond:PCl 5 , CH 4 , H 2 , CO 2 , O 2 , S 8 , SCl 2 , SiH 4 .

2 O,S 2 , N.H. 3 .

Test "Atoms of chemical elements"

Option 2

The figure shows a model of the electronic structure of an atom of a certain chemical element.

Based on the analysis of the proposed model, complete the following tasks:

1) identify the chemical element whose atom has such an electronic structure;

3) determine whether the simple substance that forms this chemical element is a metal or non-metal.

Indicate the position of nitrogen in the Periodic Table. Give its electronic formula.

Select from the list substances whose molecules contain ionic bonds:NaF, N 2 O 5 , H 2 S, KI, Cu, SO 3 , BaS.

Determine the type of chemical bond and write down the scheme of its formation for substances: Cl 2 , MgCl 2 , NCl 3 .

Determine for each isotope:

Test "Atoms of chemical elements"

Option 3

The figure shows a model of the electronic structure of an atom of a certain chemical element.

Based on the analysis of the proposed model, complete the following tasks:

1) identify the chemical element whose atom has such an electronic structure;

2) indicate the period number and group number in D.I. Mendeleev’s Periodic Table of Chemical Elements in which this element is located;

3) determine whether the simple substance that forms this chemical element is a metal or non-metal.

Indicate the position of aluminum in the Periodic Table. Give its electronic formula.

Select from the list substances whose molecules contain a polar covalent bond:O 3 , P 2 O 5 , P 4 , H 2 SO 4 , CsF, HF, HNO 3 , H 2 .

Determine the type of chemical bond and write down the scheme of its formation for substances: H 2 O, N 2 ,Na 3 S.

Determine for each isotope:

Test "Atoms of chemical elements"

Option 4

The figure shows a model of the electronic structure of an atom of a certain chemical element.

Based on the analysis of the proposed model, complete the following tasks:

1) identify the chemical element whose atom has such an electronic structure;

2) indicate the period number and group number in D.I. Mendeleev’s Periodic Table of Chemical Elements in which this element is located;

3) determine whether the simple substance that forms this chemical element is a metal or non-metal.

Indicate the position of oxygen in the Periodic Table. Give its electronic formula.

3. Substances with only ionic bonds are listed in the following series:

1) F 2 , SSl 4 , KS1;

2) NaBr, Na 2 O, KI;

3) SO 2 , P 4 ,CaF 2 ;

4) H 2 S, Br 2 , K 2 S.

4. Determine the type of chemical bond and write down the scheme of its formation for substances: CaCl 2 , O 2 , HF.

5. Determine for each isotope:

Test "Atoms of chemical elements"

Option 5

The figure shows a model of the electronic structure of an atom of a certain chemical element.

Based on the analysis of the proposed model, complete the following tasks:

1) identify the chemical element whose atom has such an electronic structure;

2) indicate the period number and group number in D.I. Mendeleev’s Periodic Table of Chemical Elements in which this element is located;

3) determine whether the simple substance that forms this chemical element is a metal or non-metal.

2. Indicate the position of carbon in the Periodic Table. Give its electronic formula.

3. In which series do all substances have a polar covalent bond?

1) HCl, NaCl, Cl 2 ;

2) O 2 , H 2 O, CO 2 ;

3) H 2 O,NH 3 , CH 4 ;

4) NaBr, HBr, CO.

4. Determine the type of chemical bond and write down the scheme of its formation for substances: Li 2 O,S 2 , N.H. 3 .

5. Determine for each isotope: