Class 11th
Get insights from 8k questions on Class 11th, answered by students, alumni, and experts. You may also ask and answer any question you like about Class 11th
Follow Ask QuestionQuestions
Discussions
Active Users
Followers
New answer posted
6 months agoContributor-Level 10
(a) Crystallisation: In this process the impure solid is dissolved in the minimum volume of a suitable solvent. The soluble impurities pass into the solution while the insoluble ones left behind. The hot solution is then filtered and allowed to cool undisturbed till crystallisation is complete. The crystals are then separated from the mother liquor by filtration and dried.
Example: crystallisation of sugar.
(b) Distillation: The operation of distillation is employed for the purification of liquids from non-volatile impurities. The impure liquid is boiled in a flask and the vapours so formed are collected and condensed to give
New answer posted
6 months agoContributor-Level 10
Inductive effect: The inductive effect refers to the polarity produced in a molecule as a result of higher electronegativity of one atom compared to another. Atoms or groups which lose electron towards a carbon atom are said to have +I Effect. Examples of +I effect are (Electron releasing)
(CH3)2C—, (CH3)2CH—, CH3CH2— CH3— etc.
Those atoms or groups which draw electron away from a carbon atom are said to have -I Effect. Examples of -I effect are:
NO2, F, Cl, Br, I, OH etc.
Electromeric effect: The electromeric effect refers to the polarity produced in a multiple bonded compound as it is approached by a reagent.
The atom A has lost
New question posted
6 months ago
New answer posted
6 months ago
Contributor-Level 10
(a) They are structural isomers. The given compounds have the same molecular formula but they differ in the position of the functional group (here ketone group: first one at C-3 and second one at C-2 positions).
(b) They are geometrical isomers. Compounds having the same molecular formula, the same constitution, and the sequence of covalent bonds, but with the different relative position of their atoms in space are called geometrical isomers.
(c) They are resonance contributors because they differ in the position of electrons but not atoms.
New answer posted
6 months agoContributor-Level 10
4.32.
Sigma bond | Pi bond |
It is formed by axial overlap of the atomic orbitals. | It is formed by the sidewise overlap of the atomic orbitals. |
The bond is quite strong. | It is a comparatively weaker bond. |
Only one lobe of the p-orbitals is involved in the overlap. | Both lobes of the p-orbitals are involved in the overlap. |
Electron cloud of the molecular orbital is symmetrical around the inter-nuclear axis. | The electron cloud is not symmetrical |
New answer posted
6 months agoContributor-Level 10
(a) Nucleophilic substitution (b) Electrophilic addition
(c) Bimolecular elimination (d) Nucleophilic substitution with rearrangement.
New answer posted
6 months agoContributor-Level 10
4.31. The electron pair involved in sharing between two atoms during covalent bonding is called shared pair or bond pair. At the same time, the electron pair which is not involved in sharing is called lone pair of electrons.
For example: CH4 has 4 bond pairs but H2O has 2 bond pairs and 2 lone pairs.
New answer posted
6 months ago
Contributor-Level 10
(a) Here, HO– acts as a nucleophile as it is an electron-rich species, i.e., it is a nucleus-seeking species.
(b) Here, –CN acts as a nucleophile as it is an electron-rich species, i.e., it is a nucleus-seeking species.
(c) CH3C+O acts as an electrophile as it is an electron deficient species.
New answer posted
6 months agoContributor-Level 10
Electrophiles: The name electrophiles mean electron loving. Electrophiles are electron deficient. They may be positive ions or neutral molecules.
Ex: H+, Cl+, Br+, NO2+, R3C+, RN2+, AlCl3, BF3
Nucleophiles: The name nucleophiles means 'nucleus loving' and indicates that it attacks the region of low electron density (positive centres) in a substrate molecule. They are electron rich they may be negative ions or neutral molecules.
Ex: Cl– Br–, CN–, OH–, RCR2–, NH3, RNH2, H2O, ROH etc.
New answer posted
6 months agoContributor-Level 10
Due to hyperconjugation, alkyl groups act as electron donors when attached to a π - system as shown below:
Taking an Exam? Selecting a College?
Get authentic answers from experts, students and alumni that you won't find anywhere else
Sign Up on ShikshaOn Shiksha, get access to
- 65k Colleges
- 1.2k Exams
- 679k Reviews
- 1800k Answers