What is the molecular structure of the molecule AlCl3?

What characteristic is notable about the structure that helps us to understand the acidic nature of AlCl3?Write a chemical reaction between AlCl3 and NH3 ignoring any reaction between AlCl3 and the solvent. Show and name the geometry of the product.

To determine the molecular structure of AlCl3 (aluminum chloride), we can refer to its Lewis structure and the concept of valence electrons.

1. Start by determining the number of valence electrons for aluminum (Al) and chlorine (Cl) atoms. Aluminum is in Group 3, so it has 3 valence electrons, while chlorine is in Group 7, hence having 7 valence electrons.

2. Since there are three chlorine atoms connected to aluminum, we multiply the valence electrons of chlorine (7 e-) by 3 to get a total of 21 electrons.

3. The aluminum atom contributes 3 valence electrons. Therefore, the total number of valence electrons for AlCl3 is 21 + 3 = 24.

4. Distribute the 24 electrons around the atoms, ensuring that octets are formed for each atom (except for hydrogen, which can have a duet).

Cl Al Cl
:Cl - Al - Cl:

5. After distributing the electrons, we can observe that each chlorine atom is bonded to the aluminum atom, and each atom has a complete octet.

The structure of AlCl3 is a trigonal planar, where the aluminum atom is surrounded by three chlorine atoms in a flat, triangular arrangement.

Regarding its acidic nature, the structure of AlCl3 suggests that it is a Lewis acid. In Lewis acid-base theory, a Lewis acid is an electron pair acceptor. The aluminum atom in AlCl3 has an incomplete octet and is missing one electron to complete it. Therefore, it readily accepts a pair of electrons, making it an acid.

Now, let's consider the reaction between AlCl3 and NH3 (ammonia). Since you asked to ignore any reaction between AlCl3 and the solvent, we'll focus on the reaction between the two compounds. The balanced equation for the reaction is as follows:

AlCl3 + 3NH3 → Al(NH3)3Cl3

In this reaction, one aluminum chloride molecule reacts with three ammonia molecules, resulting in the formation of aluminum trichloride tri-ammonia complex.

The geometry of the product, Al(NH3)3Cl3, is octahedral. It has a central aluminum atom bonded to three ammonia molecules (NH3) and three chlorine atoms (Cl) in a three-dimensional arrangement.

The molecular structure of the molecule AlCl3 is trigonal planar. In this structure, aluminum (Al) is surrounded by three chlorine (Cl) atoms. Each chlorine atom forms a single covalent bond with aluminum, resulting in a molecule with a central aluminum atom and three surrounding chlorine atoms.

The characteristic that helps us understand the acidic nature of AlCl3 is its ability to accept a lone pair of electrons. This can be observed through the Lewis acidity of the aluminum atom, which is due to an incomplete octet in its valence shell. Aluminum can accept an electron pair from a donor molecule, making it act as a Lewis acid.

Ignoring any reaction with the solvent, a chemical reaction between AlCl3 and NH3 (ammonia) can be represented by the following equation:

AlCl3 + 3NH3 → Al(NH3)3Cl3

The reaction results in the formation of the product Al(NH3)3Cl3. The geometry of the product is octahedral. This means that the central aluminum atom is surrounded by three ammonia (NH3) molecules and three chlorine (Cl) atoms, forming a symmetrical, 3D structure with a total of six surrounding atoms or groups.