The reaction between 1,3-butadiene and excess bromine in CCI4 can lead to the formation of multiple tetrabromides. Let's break down the reaction and identify the different products that can be formed.

1. Reaction overview:
1,3-butadiene (C4H6) is a conjugated diene, which means it has alternating double bonds. When it reacts with bromine (Br2) in the presence of carbon tetrachloride (CCl4), addition reactions occur at the double bonds.

2. Addition reactions:
In the presence of excess bromine, two types of addition reactions can occur at the double bonds of 1,3-butadiene:

a. Electrophilic addition: Bromine acts as an electrophile, attacking the electron-rich double bonds of the butadiene molecule. This leads to the formation of bromonium ions, which can then react with bromine or other nucleophiles.

b. Radical addition: Bromine can also undergo radical addition, where one of the bromine atoms is split into a bromine radical. This radical can then react with the double bonds of butadiene, resulting in the formation of a tetrabromide.

3. Possible tetrabromides:
Based on the addition reactions described above, three different tetrabromides can be formed:

a. 1,2,3,4-tetrabromobutane: This tetrabromide is formed when two bromine molecules add to the double bonds of 1,3-butadiene, resulting in the addition of four bromine atoms.

b. 1,2,4,5-tetrabromobutane: This tetrabromide is formed when one bromine molecule adds to the double bond at positions 1 and 4 of 1,3-butadiene, while the other bromine molecule adds to the double bond at positions 2 and 3.

c. 1,4-dibromo-2,3-dibromobutane: This tetrabromide is formed when one bromine molecule adds to the double bond at positions 1 and 4 of 1,3-butadiene, while the other bromine molecule adds to the double bond at positions 2 and 3. In this case, the bromine atoms are added in a different arrangement compared to the previous tetrabromide.

4. Conclusion:
In summary, the reaction between 1,3-butadiene and excess bromine in CCl4 can result in the formation of three different tetrabromides: 1,2,3,4-tetrabromobutane, 1,2,4,5-tetrabromobutane, and 1,4-dibromo-2,3-dibromobutane. These tetrabromides are formed due to the different addition reactions that can occur at the double bonds of 1,3-butadiene.