Class 11 Chemistry - Chapter Chemical Bonding and Molecular Structure NCERT Solutions | Write the significance/applications of d

What is meant by the term bond order? Calculate the bond order of: N₂, O₂,O₂⁺,and O₂^-.

Use molecular orbital theory to explain why the Be2 molecule does not exist.

Explain the formation of H₂ molecule on the basis of valence bond theory.

Compare the relative stability of the following species and indicate their magnetic properties:

O₂,O₂⁺,O₂^- (superoxide), O₂^2-(peroxide)

Describe the hybridisation in case of PCl₅. Why are the axial bonds longer as compared to equatorial bonds?

Which out of NH₃ and NF₃ has higher dipole moment and why?

Explain why BeH₂ molecule has a zero dipole moment although the Be–H bonds are polar.

Discuss the shape of the following molecules using the VSEPR model:

BeCl₂, BCl₃, SiCl₄, AsF₅, H₂S, PH₃

Write Lewis symbols for the following atoms and ions:

S and S2–; Al and Al3+; H and H–

Describe the change in hybridisation (if any) of the Al atom in the following reaction.

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

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

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?

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.

Calculate the mass percent of different elements present in sodium sulphate (Na₂SO₄).

Calculate the molarity of a solution of ethanol in water in which the mole fraction of ethanol is 0.040 (assume the density of water to be one).

Electrons are emitted with zero velocity from a metal surface when it is exposed to radiation of wavelength 6800 Å. Calculate threshold frequency (v₀) and work function (W₀) of the metal.

Consider the reaction of water with F₂ and suggest, in terms of oxidation and reduction, which species are oxidised or reduced.

Calculate the atomic mass (average) of chlorine using the following data:

What is the wavelength of light emitted when the electron in a hydrogen atom undergoes transition from an energy level with n = 4 to an energy level with n = 2?

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

What are the reactions involved for ozone layer depletion in the stratosphere?

Have you ever observed any water pollution in your area? What measures would you suggest to control it?

Write the expression for the equilibrium constant, K_c for each of the following reactions:

(i)   2NOCl (g)   ↔   2NO (g) + Cl₂ (g)

(ii)  2Cu(NO₃)₂ (s) ↔  2CuO (s) + 4NO₂ (g) + O₂ (g)

(iii) CH₃COOC₂H₅(aq) + H₂O(l) ↔  CH₃COOH (aq) + C₂H₅OH (aq)

(iv) Fe³⁺ (aq) + 3OH^– (aq) ↔  Fe(OH)₃ (s)

(v) I₂ (s) + 5F₂ ↔  2IF₅