Run hard@thehsc
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I know its B, but why lol?
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I know its B, but why lol?
ekjchale#1
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zinc chloride with hcl is essentially lucas's reagent, and it reacts to different extents with primary secondary and tertiaary alchols
As mentioned above, if you wish to determine whether the alcohol is primary, secondary or tertiary, you can use the Lucas test which involves the use of a Lucas’ reagent. This is essentially a solution comprised of an anhydrous zinc chloride catalyst dissolved in concentrated hydrochloric acid solution. I believe this is the reason that the correct answer to this question is (B).
Additional information in relation to the Lucas test is included below:
The Lucas test utilises zinc(II) chloride in the presence of hydrochloric acid as a reagent. In the presence of an alcohol, the Lucas reagent will halogenate the alcohol, making an insoluble product in aqueous solutions. The reaction rate for this is highly dependent on the formation of a carbocation caused by the loss of the hydroxyl as water. A carbocation formed by a primary alcohol is unstable, and thus will not readily occur. This results in no observable reaction at room temperature. A tertiary alcohol will form a stable carbocation, resulting in a rapid reaction upon the addition of the Lucas reagent. This results in a second phase appearing in the reaction mixture because the final halogenated product is insoluble in water. Secondary alcohols will form a less stable carbocation than tertiary alcohols, but the reaction will occur at room temperature in a matter of minutes. Therefore, the Lucas Test can help differentiate between primary, secondary, and tertiary alcohols.
I hope this helps!
Additional information in relation to the Lucas test is included below:
The Lucas test utilises zinc(II) chloride in the presence of hydrochloric acid as a reagent. In the presence of an alcohol, the Lucas reagent will halogenate the alcohol, making an insoluble product in aqueous solutions. The reaction rate for this is highly dependent on the formation of a carbocation caused by the loss of the hydroxyl as water. A carbocation formed by a primary alcohol is unstable, and thus will not readily occur. This results in no observable reaction at room temperature. A tertiary alcohol will form a stable carbocation, resulting in a rapid reaction upon the addition of the Lucas reagent. This results in a second phase appearing in the reaction mixture because the final halogenated product is insoluble in water. Secondary alcohols will form a less stable carbocation than tertiary alcohols, but the reaction will occur at room temperature in a matter of minutes. Therefore, the Lucas Test can help differentiate between primary, secondary, and tertiary alcohols.
I hope this helps!