: Addition of HBr to alkene involves the formation of carbocation intermediate. The carbocation is stabilized by the presence of alkyl group due to $+\mathrm{I}$ effect and presence of electron donating group. The number of $\alpha$ - hydrogen is maximum then stability of carbocation increase. Hence, the $\left(\mathrm{CH}_3\right)_2 \mathrm{C}=\mathrm{CH}_2$ is addition of $\mathrm{HBr}$ is easiest.
MPPMT-2000
Hydrocarbons
230421
Alkene which on ozonolysis yields acetone, is
230422
Baeyer's reagent decolourises which of the following?
1 Alkane
2 Alkene
3 Alkene and alkyme both
4 None of the above CGPET -2006]**
Explanation:
: Baeyer's reagent is an alkaline solution of cold potassium permanganate $\left(\mathrm{KMnO}_4\right)$ of violet colour solution. It decolourizes by alkene and alkyne both compound which decolourizes Baeyer's reagent. Baeyer's reagent will dissolve in water to give an intense violet or purple colour. It is used for detection of unsaturation in an molecule.
: Addition of HBr to alkene involves the formation of carbocation intermediate. The carbocation is stabilized by the presence of alkyl group due to $+\mathrm{I}$ effect and presence of electron donating group. The number of $\alpha$ - hydrogen is maximum then stability of carbocation increase. Hence, the $\left(\mathrm{CH}_3\right)_2 \mathrm{C}=\mathrm{CH}_2$ is addition of $\mathrm{HBr}$ is easiest.
MPPMT-2000
Hydrocarbons
230421
Alkene which on ozonolysis yields acetone, is
230422
Baeyer's reagent decolourises which of the following?
1 Alkane
2 Alkene
3 Alkene and alkyme both
4 None of the above CGPET -2006]**
Explanation:
: Baeyer's reagent is an alkaline solution of cold potassium permanganate $\left(\mathrm{KMnO}_4\right)$ of violet colour solution. It decolourizes by alkene and alkyne both compound which decolourizes Baeyer's reagent. Baeyer's reagent will dissolve in water to give an intense violet or purple colour. It is used for detection of unsaturation in an molecule.
: Addition of HBr to alkene involves the formation of carbocation intermediate. The carbocation is stabilized by the presence of alkyl group due to $+\mathrm{I}$ effect and presence of electron donating group. The number of $\alpha$ - hydrogen is maximum then stability of carbocation increase. Hence, the $\left(\mathrm{CH}_3\right)_2 \mathrm{C}=\mathrm{CH}_2$ is addition of $\mathrm{HBr}$ is easiest.
MPPMT-2000
Hydrocarbons
230421
Alkene which on ozonolysis yields acetone, is
230422
Baeyer's reagent decolourises which of the following?
1 Alkane
2 Alkene
3 Alkene and alkyme both
4 None of the above CGPET -2006]**
Explanation:
: Baeyer's reagent is an alkaline solution of cold potassium permanganate $\left(\mathrm{KMnO}_4\right)$ of violet colour solution. It decolourizes by alkene and alkyne both compound which decolourizes Baeyer's reagent. Baeyer's reagent will dissolve in water to give an intense violet or purple colour. It is used for detection of unsaturation in an molecule.
: Addition of HBr to alkene involves the formation of carbocation intermediate. The carbocation is stabilized by the presence of alkyl group due to $+\mathrm{I}$ effect and presence of electron donating group. The number of $\alpha$ - hydrogen is maximum then stability of carbocation increase. Hence, the $\left(\mathrm{CH}_3\right)_2 \mathrm{C}=\mathrm{CH}_2$ is addition of $\mathrm{HBr}$ is easiest.
MPPMT-2000
Hydrocarbons
230421
Alkene which on ozonolysis yields acetone, is
230422
Baeyer's reagent decolourises which of the following?
1 Alkane
2 Alkene
3 Alkene and alkyme both
4 None of the above CGPET -2006]**
Explanation:
: Baeyer's reagent is an alkaline solution of cold potassium permanganate $\left(\mathrm{KMnO}_4\right)$ of violet colour solution. It decolourizes by alkene and alkyne both compound which decolourizes Baeyer's reagent. Baeyer's reagent will dissolve in water to give an intense violet or purple colour. It is used for detection of unsaturation in an molecule.
