Question

Объясните, ПЖЛ, как строить углеводный скелет? А электронно-графические формулы?)))

Answer 1

В качестве примера, построить структурную формулу 2,2-диметил,4-хлор-бутана. 

1. Построить углеродный скелет. 

В данном случае, необходимо построить углеродный скелет бутана.

Бутан — C4H10

                                                 C—C—С—С

2. Обозначить номерами атомы углерода.  

                                                 1   2  3  4

                                                 С—С—С—С 

3. Отметить заместители.

В данном случае, дважды отметить метилен (—C) и хлор (—Cl)

                                                      C

                                                      |

                                                  C—C—C—CCl

                                                      |

                                                      C   

4. Наконец, отметить атомы водорода.

 

                                                    CH3 

                                                      |

                                              H3C—C—CH2—CH2Cl

                                                      |

                                                    CH3  

Answer 2

Building a Carbohydrate Skeleton

The carbohydrate skeleton refers to the arrangement of carbon atoms in a carbohydrate molecule. Carbohydrates are organic compounds composed of carbon, hydrogen, and oxygen atoms. They are classified into different types based on the number of carbon atoms they contain, such as monosaccharides, disaccharides, and polysaccharides.

The process of building a carbohydrate skeleton involves understanding the basic structure of carbohydrates and the way carbon atoms are connected. Here is a step-by-step explanation of how to build a carbohydrate skeleton:

1. Identify the type of carbohydrate: Determine whether you are working with a monosaccharide, disaccharide, or polysaccharide. Monosaccharides are the simplest form of carbohydrates and consist of a single sugar unit. Disaccharides are formed by the combination of two monosaccharides, and polysaccharides are made up of multiple monosaccharide units.

2. Determine the number of carbon atoms: Count the number of carbon atoms in the carbohydrate molecule. This will help you understand the overall structure and connectivity of the molecule.

3. Understand the basic structure: Carbohydrates have a general formula of (CH2O)n, where "n" represents the number of carbon atoms. Each carbon atom is connected to a hydrogen atom and a hydroxyl group (-OH), except for one carbon atom that is double-bonded to an oxygen atom, forming a carbonyl group (C=O).

4. Draw the backbone: Start by drawing a straight line to represent the carbon chain. The number of carbon atoms will determine the length of the backbone. For example, if you are working with a monosaccharide with five carbon atoms, draw a line with five evenly spaced points.

5. Add functional groups: Attach the appropriate functional groups to each carbon atom. Remember that each carbon atom, except for the one at the end, should have a hydroxyl group (-OH) attached. The carbon atom at the end will have a carbonyl group (C=O).

6. Connect the atoms: Connect the carbon atoms with single bonds, ensuring that each carbon atom is bonded to the appropriate number of hydrogen atoms and hydroxyl groups.

7. Add any additional groups: Depending on the specific carbohydrate, there may be additional functional groups attached to the carbon chain. These groups can vary and may include methyl groups (-CH3), amino groups (-NH2), or phosphate groups (-PO4).

8. Check the connectivity: Verify that the carbon atoms are connected correctly and that the overall structure follows the rules of organic chemistry.

Electron-Graphics Formulas

Electron-graphics formulas, also known as electron-dot structures or Lewis structures, are a way to represent the arrangement of atoms and electrons in a molecule. These formulas use dots to represent valence electrons and lines to represent chemical bonds.

To draw an electron-graphics formula for a carbohydrate molecule, follow these steps:

1. Determine the number of valence electrons: Count the total number of valence electrons for all the atoms in the molecule. Valence electrons are the electrons in the outermost energy level of an atom.

2. Identify the central atom: In most carbohydrate molecules, the central atom is carbon. However, in some cases, other elements like nitrogen or oxygen may be the central atom.

3. Place the atoms: Start by placing the central atom in the center of the drawing. Arrange the other atoms around the central atom, connecting them with single bonds.

4. Add valence electrons: Add dots around each atom to represent its valence electrons. Carbon has four valence electrons, so it will have four dots. Hydrogen has one valence electron, so it will have one dot. Oxygen has six valence electrons, so it will have six dots.

5. Complete the octets: Fill in the remaining valence electrons to complete the octet (eight electrons) for each atom, except for hydrogen, which only needs two electrons.

6. Check the connectivity: Verify that the number of valence electrons used matches the total number of valence electrons calculated in step 1. Also, ensure that each atom has a complete octet, except for hydrogen, which only needs two electrons.

It's important to note that the specific arrangement of atoms and electrons in a carbohydrate molecule can vary depending on the type of carbohydrate and its functional groups. The steps provided here are a general guideline for building a carbohydrate skeleton and drawing electron-graphics formulas.

I hope this explanation helps! Let me know if you have any further questions.