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The catalyst for the reaction of bromine with benzene is FeBr3. Why is only Fe added in the experiment? In addition, the reaction exotherm, benzene, liquid bromine are volatile, in order to reduce the effect of exotherm on benzene and liquid bromine volatile, the device should have a unique design? The produced HBr gas is easily soluble in water, how should it be absorbed and tested? The catalyst for the reaction of bromine and benzene is FeBr3. Why is only Fe added in the experiment? In addition, the reaction exotherm, benzene, liquid bromine are volatile, in order to reduce the effect of exotherm on benzene and liquid bromine volatile, the device should have a unique design? The produced HBr gas is easily soluble in water, how should it be absorbed and tested?
Liquid bromine reacts with iron to form iron bromide.
It can be done in an ice bath.
Connect a condenser and collect again.
How to analyze the valence of each element in organic compounds?
If you are a beginner in chemistry, you can judge the valence of C by thinking that H is +1 valence, O is -2 valence and the valence of compound is 0. If you are not a beginner, please look down.
Electron pair bias is the electronegativity of an element, H =2.1, C =2.5, O =3.5.
The C-H bond electrons are therefore biased towards C, while the C-O bond electrons are biased towards O
Example: CH4
Common electron pairs of C-H covalent bonds are biased towards C, so C is negatively charged
Example: HCOOH
C is connected to one H, so the electrons of the C-H bond are biased toward C, and the other side of C has two Os, which is attractive to the electrons of C, so most of the electrons of the other side of C are biased toward O, so C is generally positive.
This is just a simple overview.
Note: The above electrons refer to the outermost electrons
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