Class 11 Chemistry - Chapter Environmental Chemistry NCERT Solutions | List gases which are responsible for gre

Carbon monoxide gas is more dangerous than carbon dioxide gas. Why?

What are the harmful effects of photochemical smog and how can they be controlled?

Write down the reactions involved during the formation of photochemical smog.

Explain tropospheric pollution in 100 words.

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

What would have happened if the greenhouse gases were totally missing in the earth's atmosphere? Discuss.

Statues and monuments in India are affected by acid rain. How?

What do you mean by green chemistry? How will it help decrease environmental pollution?

What is smog? How is classical smog different from photochemical smog?

What do you mean by ozone hole? What are its consequences?

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?

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?

The type of hybridisation of boron in diborane is

(a) sp    (b) sp²   (c) sp³    (d) dsp²

In three moles of ethane (C₂H₆), calculate the following:
(i) Number of moles of carbon atoms.
(ii) Number of moles of hydrogen atoms.
(iii) Number of molecules of ethane.

Following results are observed when sodium metal is irradiated with different wavelengths.

Calculate (a) threshold wavelength and, (b) Planck’s constant.

Does the number of moles of reaction products increase, decrease or remain same when each of the following equilibria is subjected to a decrease in pressure by increasing the volume?

(a) PCl₅ (g) ↔ PCl₃ (g) + Cl₂ (g)

(b) CaO (s) + CO₂ (g) ↔ CaCO₃ (s)

(c) 3Fe (s) + 4H₂O (g) ↔ Fe₃O₄ (s) + 4H₂ (g)

Although geometries of NH₃ and H₂O molecules are distorted tetrahedral, bond angle in water is less than that of ammonia. Discuss.

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.

Explain, why an organic liquid vaporises at a temperature below its boiling point in its steam distillation?

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.

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

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