Class 11 Chemistry - Chapter Organic Chemistry Some Basic Principles and Techniques NCERT Solutions | Why is a solution of potassium hydroxide

What are hybridisation states of each carbon atom in the following compounds ?

(i) CH₂=C=O,

(ii) CH₃CH=CH₂,

(iii) (CH₃)₂CO,

(iv) CH₂=CHCN,

(v) C₆H₆

Explain the terms Inductive and Electromeric effects. Which electron displacement effect explains the following correct orders of acidity of the carboxylic acids?

(a) Cl₃CCOOH > Cl₂CHCOOH > ClCH₂COOH

(b) CH₃CH₂COOH > (CH₃)₂CHCOOH > (CH₃)₃C.COOH

Write bond line formulas for : Isopropyl alcohol, 2,3-Dimethyl butanal, Heptan-4- one.

Give condensed and bond line structural formulas and identify the functional group(s) present, if any, for :

(a) 2,2,4-Trimethylpentane

(b) 2-Hydroxy-1,2,3-propanetricarboxylic acid

(c) Hexanedial

Indicate the σ and π bonds in the following molecules :

(i) C₆H₆,

(ii) C₆H₁₂,

(iii) CH₂Cl₂,

(iv) CH₂=C=CH₂,

(v) CH₃NO₂,

(vi) HCONHCH₃

Identify the reagents shown in bold in the following equations as nucleophiles or electrophiles:

(a) CH₃COOH  +  HO^-  →   CH₃COO^- + H₂O

(b) CH₃COCH₃  +  C^-N  →  (CH₃)₂ C (CN) (OH)

(c) C₆H₅  +  CH₃C⁺O  →  C₆H₅COCH₃

For the following bond cleavages, use curved-arrows to show the electron flow and classify each as homolysis or heterolysis. Identify reactive intermediate produced as free radical, carbocation and carbanion.

Which of the following represents the correct IUPAC name for the compounds concerned?
(a) 2,2-Dimethylpentane or 2-Dimethylpentane
(b) 2,4,7-Trimethyloctane or 2,5,7-Trimethyloctane
(c) 2-Chloro-4-methylpentane or 4-Chloro-2-methylpentane
(d) But-3-yn-1-ol or But-4-ol-1-yne

Draw the resonance structures for the following compounds. Show the electron shift using curved-arrow notation.

(a) C₆H₅OH

(b) C₆H₅NO₂

(c) CH₃CH=CHCHO

(d) C₆H₅–CHO

(e) C₆ H₅ - C⁺H₂ 

(f)  CH₃CH = CHC⁺H₂

Which of the following carbocation is most stable ?

How do you account for the formation of ethane during chlorination of methane?

What will be the minimum pressure required to compress 500 dm³ of air at 1 bar to 200 dm³ at 30°C?

What are the common physical and chemical features of alkali metals?

Calculate the molecular mass of the following:
(i) H₂O
(ii) CO₂
(iii) CH₄

Assign oxidation number to the underlined elements in each of the following species:

(a) NaH₂PO₄

(b) NaHSO₄

(c) H₄P₂O₇

(d) K₂MnO₄

(e) CaO₂

(f) NaBH₄

(g) H₂S₂O₇

(h) KAl(SO₄)₂.12 H₂O

What is the basic theme of organisation in the periodic table?

Explain the formation of a chemical bond.

Choose the correct answer. A thermodynamic state function is a quantity
(i) used to determine heat changes
(ii) whose value is independent of path
(iii) used to determine pressure volume work
(iv) whose value depends on temperature only.

A liquid is in equilibrium with its vapour in a sealed container at a fixed temperature. The volume of the container is suddenly increased.
a) What is the initial effect of the change on vapour pressure?
b) How do rates of evaporation and condensation change initially?
c) What happens when equilibrium is restored finally and what will be the final vapour pressure?

Justify the position of hydrogen in the periodic table on the basis of its electronic configuration.

What does atomic radius and ionic  radius really mean to you?

Arrange the following metals in the order in which they displace each other from the solution of their salts.

Al, Cu, Fe, Mg and Zn.

Use the data given in the following table to calculate the molar mass of naturally occurring argon isotopes:

State as to why

(a) a solution of Na₂CO₃ is alkaline ?

(b) alkali metals are prepared by electrolysis of their fused chlorides ?

(c) sodium is found to be more useful than potassium ?

How will you convert benzene into

(i) p - nitrobromobenzene

(ii) m - nitrochlorobenzene

(iii) p - nitrotoluene

(iv) acetophenone?

Explain with the help of suitable example polar covalent bond.

How many neutrons and protons are there in the following nuclei?

An atom of an element contains 29 electrons and 35 neutrons.
Deduce (i) the number of protons and (ii) the electronic configuration of the element.

(i) Calculate the number of electrons which will together weigh one gram.
(ii) Calculate the mass and charge of one mole of electrons.

The ejection of the photoelectron from the silver metal in the photoelectric effect experiment can be stopped by applying the voltage of 0.35 V when the radiation 256.7 nm is used. Calculate the work function for silver metal.