Class 12th
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New answer posted
a year agoContributor-Level 10
a )Tollen's test –Due to oxidizing nature of aldehydes they get easily oxidized, wheareas in case of ketones they are not readily
oxidizable. And tollens test exploits this fact, [Ag (NH3)2]+ is used as reagent Ag mirror is formed during this reaction
b) fehling test- aldehyde reduces the fehling solution to form red brow precipitate of Cu2O. Fehling's solution is a chemical reagent used to differentiate between water-soluble carbohydrate and ketone functiona groups, and as a test for reducing sugars and non-reducing sugars, supplementary to the Tollens' reagent test.
2. Iodoform te
New answer posted
a year agoContributor-Level 10
1. Di-tertbutyl, ketone 2. +I effect donates e- . Br group will show +I effect along the chain but as I effect is distance dependent effect it will die as the distance increase.+I effect of alkyl group will reduce the acidity of a compound whereas –I effect will increase the acidity, I effects are distance dependent, correct order will be (CH3)2CHCOOH< CH3CH2CH2COOH< CH3CH (Br)CH2COOH < CH3CH2CH (Br)COOH. 3. As we know the electron releasing groups (ERG) reduces the acidic strength of the compound (via inductive effect) whereas the electron withdrawing group (EWG) will increase the acidic strength of compound, and methoxy group is
New answer posted
a year agoContributor-Level 10
ANSWER: Given compound is having 8 carbons, and on reaction with chromic acid C is converted back into B, as chromic acid reaction couldn't add any carbon hence both alcohol and acid must contain 4 carbons and it is given in the question that on dehydration C will give but-1-ene so alcohol will be butan-1-ol (C) and acid will be butan-1-oic acid (B) and given reaction will be ester hydrolysis,
New answer posted
a year agoContributor-Level 10
The image is real when it is formed by the actual convergence of rays and it can be projected on a screen. For example, when the object is placed beyond focus, and the image is formed either by the convex lens or concave mirror.
The image is virtual, if it is formed by the apparent divergence of rays and it cannot be captured on a screen. For example, when the image is formed by the convex mirror or plane mirror.
New answer posted
a year agoContributor-Level 10
Since the given compound with molecular formula C9H10O form a 2,4-DNP derivative and reduce Tollen's reagent, it must be an aldehyde. Since it undergoes cannizzaro reaction, therefore CHO group is directly attached to the benzene ring.
Since on vigorous oxidation, it gives 1,2-benzene dicarboxylic acid, therefore it must be ortho-substituted benzaldehyde. The only o-substituted aromatic aldehyde having molecular formula C9H10O is o—ethyl benzyldehyde all the reaction can show now be explained on the basis of this structure-
New answer posted
a year agoContributor-Level 10
Simple microscope: When the object is placed within the focal length, the simple microscope works on the principle of producing an erect, virtual and magnified image. To magnify small objects, the simple microscope uses a single convex lens.
Compound microscope: It uses two lenses including an eyepiece and objective. The objective lens creates a real, magnified, and inverted image which acts as the object for the eyepiece, which in turn magnifies it further.
New answer posted
a year agoContributor-Level 10
i) Taking two molecules of propanal, one which acts as a nucleophile and the other as an electrophile.
(iii) Taking one molecule each of propanal and butanal in which propanal acts as a nucleophile and butanal acts as an electrophile.
New answer posted
a year agoContributor-Level 10
In Ray Optics And Optical Instruments questions, when using lens and mirror formulas, sign convention helps in maintaining consistency. The sign convention determines whether quantities like image distance, object distance, and focal length are taken as positive or negative. The incorrect usage of these sign conventions mostly leads to wrong magnifications and image positions. For accurate results, it is essential to follow the Cartesian sign.
New answer posted
a year agoContributor-Level 10
1. Butane-1,3-diol -
Ethanol react dilute alkali produces 3-hydroxybutanal which on Reduction gives butane-1, 3-diol on reduction.
New answer posted
a year agoContributor-Level 10
Ans
Aldehydes and ketones having at least one α-hydrogen undergo aldol The compounds
(ii) 2-methylpentanal
(v) cyclohexanone
(vi) 1-phenylpropanone
(vii) phenylacetaldehyde
contain one or more α-hydrogen atoms. Therefore, these undergo aldol condensation.
Aldehydes having no α-hydrogen atoms undergo Cannizzaro The compounds
(i) Methanal
(iii) Benzaldehyde
(ix) 2, 2-dimethylbutanal
do not have any α-hydrogen. Therefore, these undergo cannizzaro reactions.
Compound (iv) Benzophenone is a ketone having no α-hydrogen atom and compound (viii) Butan-1-ol is an alcohol. Hence, these compounds do not undergo either aldol condensation or canni
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