Class 11 Chemistry - Chapter Environmental Chemistry NCERT Solutions | Write down the reactions involved during

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?

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?

A large number of fish are suddenly found floating dead on a lake. There is no evidence of toxic dumping but you find an abundance of phytoplankton. Suggest a reason for the fish kill.

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?

Among the following pairs of orbitals which orbital will experience the larger effective nuclear charge?

(i) 2s and 3s,

(ii) 4d and 4f,

(iii) 3d and 3p

Why does benzene undergo electrophilic substitution reactions easily and nucleophilic substitutions with difficulty?

Discuss the pattern of variation in the oxidation states of
(i) B to Tl and (ii) C to Pb.

Write the general outer electronic configuration of s-, p-, d- and f- block elements.

What is the basic difference in approach between the Mendeleev’s Periodic Law and the Modern Periodic Law?

Write the complete symbol for the atom with the given atomic number (Z) and Atomic mass (A)

(i) Z = 17, A = 35

(ii) Z = 92, A = 233

(iii) Z = 4, A = 9

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

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

How do you expect the metallic hydrides to be useful for hydrogen storage? Explain.

Why does the following reaction occur ?

XeO^4– _6(aq)  +  2F ^– _(aq) + 6H ⁺ _(aq)  →   XeO_3(g)  +  F_2(g) + 3H₂O_(l)

What conclusion about the compound Na₄XeO₆ (of which XeO^4– 6 is a part) can be drawn from the reaction.