The conversion(s) that can be carried out by bromine in carbon tetrachloride solvent is/are
- PhCH=CHCH3\(\rightarrow\)PhCHBrCHBrCH3
- CH3CH2COOH\(\rightarrow\)CH3CHBrCOOH
The Correct Option is A, D
Solution and Explanation
There are two common qualitative methods used to test for unsaturation in compounds: the reaction with bromine in carbon tetrachloride and the reaction with potassium permanganate. In both instances, a positive outcome is indicated by the fading of color in the reagent.
In the bromine in carbon tetrachloride test, alkenes containing carbon-carbon double bonds and alkynes featuring carbon-carbon triple bonds react with bromine, leading to the formation of dibromoalkanes and tetrabromoalkanes, respectively. This reaction consumes molecular bromine, causing its distinctive dark red-brown hue to vanish if bromine is not excessively added. The swift disappearance of the bromine color confirms the presence of unsaturation.
The second qualitative test, known as the Baeyer test, employs potassium permanganate. This test relies on the oxidation capability of potassium permanganate to convert carbon-carbon double bonds into alkanediols or carbon-carbon triple bonds into carboxylic acids, thereby identifying unsaturation.
It's worth noting that only ethene gas exhibits positive results for both tests, while ethane does not display these reactions.
The correct answer is option(s):
(A): PhCH=CHCH3\(\rightarrow\)PhCHBrCHBrCH3
(D): 
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Concepts Used:
Alkanes
In organic chemistry, an alkane, or paraffin (a historical trivial name that also has other meanings), is an acyclic saturated hydrocarbon. In other words, an alkane consists of hydrogen and carbon atoms arranged in a tree structure in which all the carbon-carbon bonds are single. Alkanes have the general chemical formula CnH2n+2. The alkanes range in complexity from the simplest case of methane (CH4), where n = 1 (sometimes called the parent molecule), to arbitrarily large and complex molecules, like pentacontane (C50H102) or 6-ethyl-2-methyl-5-(1-methylethyl) octane, an isomer of tetradecane (C14H30).
Alkane as saturated hydrocarbons:
- Alkanes are a series of compounds that contain carbon and hydrogen atoms with single covalent bonds. These are known as saturated hydrocarbons. This group of compounds consists of carbon and hydrogen atoms with single covalent bonds. Also comprises a homologous series having a molecular formula of CnH2n+2.
- Alkanes are the simplest family of hydrocarbons. They contain only carbon and hydrogen. Each carbon atom forms four bonds and each hydrogen atom forms one bond. Chemists use line-angle formulas because they are easier and faster to draw than condensed structural formulas. Structural formulas for alkanes can be written in yet another condensed form.
Properties of Alkanes:
1. The Solubility of Alkanes
Due to very little difference of electronegativity between carbon and hydrogen and covalent nature of C-C bond or C-H bond, alkanes are generally non-polar molecules.As we generally observe, polar molecules are soluble in polar solvents whereas non-polar molecules are soluble in non-polar solvents. Hence, alkanes are hydrophobic in nature that is, alkanes are insoluble in water.
2. The Boiling Point of Alkanes
As the intermolecular Van Der Waals forces increase with the increase of the molecular size or the surface area of the molecule we observe:The straight-chain alkanes are observed to have a higher boiling point in comparison to their structural isomers.
3. The Melting Point of Alkanes
The melting point of alkanes follow the same trend as their boiling point that is, it increases with increase in molecular weight.