In synthesizing tert-butyl chloride using tert-butyl alcohol and concentrated HCl...?

Question

1. when the tert-butyl chloride and HCl have been mixed into the separatory funnel, It must be shaken vigorously. Then, venting. What is the purpose of venting?

2. When the layers are clearly separated, drain the HCl layer into the beaker.
While the upper layer (raw tert-butyl chloride) is poured into the erlenmeyer flask. After that, dehydrate Calcium Chloride (CaCl2)are added to the raw tert-butyl chloride.

What is the function of dehydrate CaCl2?
Is it as a catalyst?
Does it reacts with the raw tert-butyl chloride?

3- Why primary and secondary alkyl halide are not synthesized during this method? Explain plz.

4- Why is the percentage of the yield in this experiment is less than 100%? Does the sample contains impurities? Explain.

Thanks for those who's answering me.
A lot of thanks

Answer 1

1. to release any excess pressure - for example by HCl gas.

2. It's a drying agent, to remove any water.

3. The carbon chain does not re-arrange itself. You can only put a -Cl group where the -OH group was.

4. The reaction will not go to completion, so the product will contain some unreacted alcohol.

Answer 2

the guy above me is right about everything but the theres a few point he could have explained better.

primary and secondary alcohol will not undergo a sn1 reaction (this is a first order nucleophilic reaction) where the leaving group (OH ) leaves before the Cl can attact to the carbocation.

and 100% yield is near impossible and the effectiveness of the reaction is usually judged on how your yield compares to similar reactions>