Explain why Grignard reagents do not reacts with alkanes.

Explain why Grignard reagents do not reacts with alkanes.
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Answer :

Ans. In alkanes , the C – H bond has very little polarity . The hydrogen cannot be abstracted by the Grignard reagent.
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Which of the following reagents will react readily with both aldehydes and ketones? (a) Grignard reagent (b) Fehling's reagent (c) Tollens' reagent (d) Schiff's reagen

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Ketones react with Grignard reagents to form an addition product which on hydrolysis gives a (a) Primary alcohol (b) Tertiary alcohol (c) Secondary alcohol (d) Ketal

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Grignard reagents do not show any reaction with (a) Alkoxyalkanes (b) Alkanones (c) Alkyl alkanoates (d) Acyl halides

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Last Answer : Alkoxyalkanes

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Last Answer : None of the above are correct.

Phenol reacts with which one of the following reagents gives a conjugate diketone will be formed ?

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Last Answer : A Grignard reagent is added to a carboxylic acid

Which of the following alcohols can be prepared by the reaction of methyl formate with excess Grignard reagent? (a) 1-pentanol (b) 2-pentanol (c) 3-pentanol (d) 2-methyl-2-pentanol

Description : Which of the following alcohols can be prepared by the reaction of methyl formate with excess Grignard reagent? (a) 1-pentanol (b) 2-pentanol (c) 3-pentanol (d) 2-methyl-2-pentanol

Last Answer : 3-pentanol

The disappearance of the purple color of KMnO4 in its reaction with alkene is known as (a) Markovnikov test (b) Grignard test (c) Baeyer test (d) Wurtz test

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Last Answer : Baeyer test

Whose name is given to alkylmagnesium halides: w) Victor Grignard x) Daniel Rutherford y) Dmitri Mendeleev

Description : Whose name is given to alkylmagnesium halides: w) Victor Grignard x) Daniel Rutherford y) Dmitri Mendeleev

Last Answer : ANSWER: W -- VICTOR GRIGNARD

The modern atomic theory was conceived by : w) Victor Grignard x) Daniel Rutherford y) Svante Arrhenius z) John Dalton

Description : The modern atomic theory was conceived by : w) Victor Grignard x) Daniel Rutherford y) Svante Arrhenius z) John Dalton

Last Answer : ANSWER: Z -- JOHN DALTON

Grignard reagent is chemically known as (A) Ethyl magnesium chloride (B) Methyl magnesium chloride (C) Dichlorophenol (D) Monochloroacetic acid

Description : Grignard reagent is chemically known as (A) Ethyl magnesium chloride (B) Methyl magnesium chloride (C) Dichlorophenol (D) Monochloroacetic acid

Last Answer : (A) Ethyl magnesium chloride

Chemical name of Grignard reagent is (A) Sodium thiosulphate (B) Ethyl magnesium chloride (C) Sodium sulphite (D) Sodium bicarbonate

Description : Chemical name of Grignard reagent is (A) Sodium thiosulphate (B) Ethyl magnesium chloride (C) Sodium sulphite (D) Sodium bicarbonate

Last Answer : (B) Ethyl magnesium chloride

(4) None of these Explanation: Catalysis is the change in rate of a chemical reaction due to the participation of a substance called a catalyst. Unlike other reagents that participate in the chemical reaction, a catalyst is not consumed by the reaction itself. A catalyst may participate in multiple chemical transformations. Catalysts that speed the reaction are called positive catalysts.

Description : (4) None of these Explanation: Catalysis is the change in rate of a chemical reaction due to the participation of a substance called a catalyst. Unlike other reagents that ... may participate in multiple chemical transformations. Catalysts that speed the reaction are called positive catalysts.

Last Answer : Table salt gets moist during rainy season because – (1) sodium chloride is hygroscopic (2) sodium chloride is deliquescent (3) sodium chloride contains some quantity of sodium iodide (4) sodium chloride contains hygroscopic impurities like magnesium chloride

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Description : Which of the following reagents will react with furan to form 2-furansulfonic acid? (a) SO3 in pyridine at 100°C (b) Dilute H2SO4 at 200°C (c) SO2 at 100°C (d) Dilute H2SO4 at 100°C

Last Answer : SO3 in pyridine at 100°C

Which of the following reagents will react with pyrrole to form 2- formylpyrrole? (a) HCOOH (b) CHCl3/KOH (c) H2O2 (d) (CH3CO)2O/SnCl4

Description : Which of the following reagents will react with pyrrole to form 2- formylpyrrole? (a) HCOOH (b) CHCl3/KOH (c) H2O2 (d) (CH3CO)2O/SnCl4

Last Answer : CHCl3/KOH

Which of the following reagents is used to prepare benzenediazoniumchloride from aniline?(a) NaNO2 + HCl(b) LiAlH4(c) NH2NH2 + KOH(d) NaOH

Description : Which of the following reagents is used to prepare benzenediazonium chloride from aniline? (a) NaNO2 + HCl (b) LiAlH4 (c) NH2NH2 + KOH (d) NaOH

Last Answer : NaNO2 + HCl

Which of the following reagents does not react with aniline? (a) Acetyl chloride (b) Acetic anhydride (c) Ammonia (d) Nitrous acid

Description : Which of the following reagents does not react with aniline? (a) Acetyl chloride (b) Acetic anhydride (c) Ammonia (d) Nitrous acid

Last Answer : Ammonia

Which of the following reagents can be used to distinguish between chlorobenzene and benzyl chloride? (a) alcoholic AgNO3 (b) Br2 in CCl4 (c) KCN (d) Br2 in H2O

Description : Which of the following reagents can be used to distinguish between chlorobenzene and benzyl chloride? (a) alcoholic AgNO3 (b) Br2 in CCl4 (c) KCN (d) Br2 in H2O

Last Answer : alcoholic AgNO3

Which of the following reagents can be used to distinguish between chlorobenzene and allyl chloride? (a) H2/Ni(b) Br2 in CCl4(c) Zn/HCl(d) NH2NH2

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Last Answer : Br2 in CCl4

Which of the reactions between the following pairs of reagents proceeds by a mechanism that may be described as an electrophilic substitution? (a) Benzene + Br2/FeBr3 (b) Propene + Br2 (c) Acetone + NH2NH2 (d) Ethyl bromide + aq KOH

Description : Which of the reactions between the following pairs of reagents proceeds by a mechanism that may be described as an electrophilic substitution? (a) Benzene + Br2/FeBr3 (b) Propene + Br2 (c) Acetone + NH2NH2 (d) Ethyl bromide + aq KOH

Last Answer : Benzene + Br2/FeBr3

Which of the following reagents is most suitable for preparing chlorobenzene from benzene? (a) Aqueous chlorine (b) Chlorine in the presence of ultraviolet light (c) Chlorine in acetic acid (d) Chlorine in the presence of FeCl3

Description : Which of the following reagents is most suitable for preparing chlorobenzene from benzene? (a) Aqueous chlorine (b) Chlorine in the presence of ultraviolet light (c) Chlorine in acetic acid (d) Chlorine in the presence of FeCl3

Last Answer : Chlorine in the presence of FeCl3

Which of the following reagents will react with methyl group rather than thebenzene ring in methylbenzene?(a) Chlorine in the presence of uv light(b) CH3Cl in the presence of AlCl3(c) CH3COCl in the presence of AlCl3(d) Hydrogen in the presence of nickel

Description : Which of the following reagents will react with methyl group rather than the benzene ring in methylbenzene? (a) Chlorine in the presence of uv light (b) CH3Cl in the presence of AlCl3 (c) CH3COCl in the presence of AlCl3 (d) Hydrogen in the presence of nickel

Last Answer : Chlorine in the presence of uv light