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Chipko movement is a non-violent response led by peasant women to the large-scale deforestation that was taking place in the Himalayan region.

Vandana Shiva started the ‘Navdanya’ movement for biodiversity conservation and organic farming in 1987.

Answer is (i), (iv)

Answer is (ii), (iii)

i) Spherical shaped sub-shell “l” value is zero and symbol is ‘s’. 

ii) Number of m; values for 1 = 2 is 5, those are -2, -1, 0, 1, 2. 

iii) Symbols of the orbitals for l = 1 sub shell are p_x, p_y, p_z. 

iv) Shape of the subshell l = 2 is double dumbel. 

The maximum number of electrons that can occupy in this sub-shell is 10.

(a) Methanoicacid – Formic acid

(b) Ethanoic acid – Acetic acid

0.02% of carbon in earth's crust.

The general molecular formula of an alkane is written as C_nH_2n+2, and the general formula of an alkene is written as C_nH_2n where ‘n’ is the number of carbon atoms. 

Now for n=20, the molecular formula of 

a) Alkane will be C₂₀H_2x20+2 or C₂₀H₄₂ 

b) Alkene will be C₂₀H_2x20 or C₂₀H₄₀

Plants, wood, natural gas, coal, petroleum, etc. are the natural sources of carbon compounds.

The chemistry of carbon compounds (excluding the carbonates, bicarbonates, carbides, cyanides, carbon dioxide, and carbon monoxide) is called organic chemistry. The large number of organic compounds necessitated their study in separate branch of chemistry, known as organic chemistry,

(a) A group of organic compounds having the same functional group and similar structures in which any two successive members differ by - CH₂.

(b) (i)All members have Similar chemical properties

(ii) There is gradation in the physical properties.

(c) Name - Ethanoic acid/Acetic acid

Formula- CH₃COOH

Acetic acid ( CH₃COOH) is a weaker acid because it does not dissociate completely into its ions in aqueous solution. 

Activity: Add zinc metal in HCI and CH₃COOH respectively. The hydrogen gas will be evolved faster in HCI and slowly in CH₃COOH. It shows acetic acid is a weak acid. 

Alternative Method:

 If we use pH paper, the colour of pH paper will be dark red in HCI and light red in CH₃COOH which shows HCI is a strong acid and CH₃COOH is a weak acid.

Methanol is the simplest alcohol, It is the first member of the homologous series of alcohol. It is also known as wood alcohol, as it was initially obtained by the destructive distillation of wood.

When methanol is consumed, it is oxidised to methanal in the liver. Methanal reacts rapidly with the components of cell, leading to the coagulation of protoplasm. Consumption of methanol can also damage the optic nerve, resulting in blindness.

A group of organic compounds which can be represented by the same general formula with a same functional group and which show more or less similar trends in their properties is known as homologous series.

Example: The homologous series of straight chain alkanes can be represented by the general formula C_n​H_2n+2​ 

Thus the first four members of alkane homologous series are CH₄​ (methane),

CH₃​−CH₃​ (Ethane),  CH₃​−CH₂​−CH₃​ (propane) and  CH₃​−CH₂​−CH₂​−CH₃​ (butane).

Characteristics of a homologous series are:

(i) Each member of the series can be represented by a general formula.

(ii) All the members of the series can be prepared by the same general methods.

(iii) Physical properties changes throughout the series in a regular way.

(iv) Members of homologous series have similar chemical properties.

1. The series of carbon compounds in which two successive compounds differ by – CH₂ unit is called homologous series. 

Ex : 1) CH₄, C₂ H₆, C₃ H₈, ……………….. 

2) CH₃OH, C₂H₅OH, C₃H₇OH, ……………….. 

2. If we observe above series of compounds, we will notice that each compound in the series differs by – CH₂ unit by its successive compound.

3. Characteristics of homologous series : 

i) They have one general formula. 

Ex : alkanes (C_nH_2n+2), alkynes (C_nH_2n-2), alcohols (C_n H_2n+1) OH, etc. 

ii) Successive compounds in the series possess a difference of (CH₂) unit. 

iii) They have similar chemical properties.

Correct option is  A) Vinegar

The series of organic compounds having same functional group and similar chemical properties is called homologous series. Each member differs from successive member by —CH₂— group. The difference in molecular weight between two successive members is 14 u. 

Characteristics:

(i) It has same general formula, from which, all members can be derived. 

(ii) They have similar chemical properties. C₂H₄, CH₂=CH₂, Ethene is first member of alkene series.

Amino is the prefix used for -NH Group

Correct option is  A) Alcohol

Characteristics of homologous series :

1. They have one general formula. 

e.g.: Alkanes (C_n H_2n+2 ) 

2. Successive compounds in the series possess a difference of – CH₂ unit. 

3. They possess similar chemical properties due to same functional group. 

e.g.: C – OH 

4. They show a regular gradation in their physical properties.

Nomenclature of organic chemistry is systematic method of naming organic compound.

Correct option is  B) Ethyne

Correct option is  C) amine

Word root: 

Word root indicates the number of carbon atoms in the longest possible continuous carbon chain also known as parent chain.

1) Primary Suffix : 

It is used to indicate the degree of saturation or unsaturation of the main chain.

2) Secondary Suffix : 

It is used to indicate the main functional group in the organic compound.

Features of Organic Compounds

1. Types of Linkages – Organic compounds generally contain covalent linkages while Inorganic Compounds are ionic in nature.

2. Melting and Boiling Point – Organic Compounds have low melting and boiling points because of their covalent nature. Inorganic Compounds usually have high melting and boiling points.

3. Solubility – Organic Compounds are insoluble in water but soluble in organic solvents.

4. Electrical Conductivity – Organic Compounds are bad conductors of electricity while inorganic compounds are good conductors of electricity.

5. Nature of reactions – Organic reactions are complicated and slow whereas Inorganic reactions are instantaneous.

6. Stability – Organic Compounds are less stable to heat than Inorganic Compounds.

7. Combustibility – Organic Compounds are combustible and generally leave no residue, when burnt. Inorganic Compounds are incombustible.

A. (iii)

B. (iv)

C. (v) 

D. (ii)

E. (i)

• Soaps are the sodium or potassium salts of long chain carboxylic acids while detergents are the ammonium of sulphonate salts of long chain carboxylic acids.
• The dirt is oily in nature and when soap is added to water, its molecules form structures called micelles in which carbon chain of the molecules dissolves in the oil while the ionic end dissolves in water and faces outside. The micelles thus help in dissolving the dirt in the water. 
• Ca²⁺ and Mg²⁺ present in hard water form insoluble substance (scum) with soap.
•  Two problems :

(i) Non-biodegradable

(ii) Water pollution/soil pollution

Cleansing Action of  Soap : When soap is dissolved in water, it forms a colloidal suspension. In this colloidal suspension, the soap molecules cluster together to form micelles and remain radially suspended in water with the hydrocarbon end towards the centre and the ionic end directed outward. The dirt particles always adhere to the oily or greasy layer present on the skin or clothes. When a dirty cloth is dipped into a soap solution, its nonpolar hydrocarbon end of micelles gets attached to the grease or oil present in dirt and polar end remains in the water layer.

The mechanical action of rubbing subsequently dislodges the oily layer from the dirty surface shaping it into small globules. A stable emulsion of oil in water is formed. The emulsified oil or grease globules bearing the dirt can now be readily washed with water.

Soaps do not form lather when the water is hard. When soap is added to hard water, calcium and magnesium salts present in water displace sodium or potassium ions from the soap molecules forming an insoluble substance called scum.

Problems that arise due to use of detergents instead of soap :

(i) Detergents being non-biodegradable, they accumulate in the environment causing pollution.

(ii) In soil, the presence of detergents leads to pH changes making soil infertile.

(iii) The entry of detergents into food chain leads to bioaccumulation in living beings and tends toward serious health issues.

C₃H₆, H₂C=CH—CH₃ 

Propene is second member of series whose general formula is C_nH₂n.

(a) y and w 

(b) Alfred Sturtevant 

(c) Crossing over rarely takes between genes

Correct option is  B) — al

It is Alcohol

Saturated Carbon Compounds

Compounds of carbon and hydrogen whose adjacent carbon atoms contain only one (carbon-carbon) bond are known as saturated hydrocarbons. Their carbon-hydrogen bonds are also single covalent bonds. They are called saturated compounds because all the four bonds of carbon are fully utilised and no more hydrogen or other atoms can attach to it. Thus, they can undergo only substitution reactions. They are also representative of open-chain aliphatic hydrocarbons. These saturated hydrocarbons are called as alkanes.

Unsaturated Hydrocarbons

Compounds of carbon and hydrogen that contain one double covalent bond between carbon atoms (carbon=carbon) or a triple covalent bond between carbon atoms (C ≡ C) are called unsaturated hydrocarbons. In these molecules, since all the bonds of carbon are not fully utilised by hydrogen atoms, more of these can be attached to them. Thus, they undergo addition reactions (add on hydrogen) as they have two or more hydrogen atoms less than the saturated hydrocarbons (alkanes).

Unsaturated hydrocarbons can be divided into 'alkenes' and 'alkynes' depending on the presence of double or triple bonds respectively.

(a) Assertion and Reason are correct, Reason explains the Assertion.

• Detergents are better than soaps because detergents are ammonium or sulphonate salts of long chain carboxylic acids.
• Charged ends of theses will not for precipitate with calcium and magnesium present in hard water. 
• On the other hand soaps will form precipitate with calcium and magnesium ions present in the hard water.

The general formula for alkanes is CnH_2n+1–CHO. The value of ‘n’ for the first member is 0.

(a) Sex linked inheritance 

(b) Mendelian disorder is determined by mutation in the single gene.

These disorders are transmitted to o springs in the same line as the principles of inheritance.

The secondary suffix used in IUPAC nomenclature of an aldehyde is -al

Rules to be followed

i) Longest carbon chain is selected, 

ii) Chain is numbered in such a way that the branched chain or substituent gets the smallest number, 

iii) If the functional group is present, it is given the. lowest number, 

iv) Substituents are named in the alphabetical order, 

v) The position of substituents are prefixed with hyphen, 

vi) Multiple substituents are written with numerical prefixes such as di or tri.

Name and the general formula of hydrocarbons undergoing addition reaction with hydrogen :

Detergents chemically are sodium or potassium salts of sulphonic acid of benzene or alkene. 

Merits: 

(i) They work well with hard water. 

(ii) They are more effective than soaps. 

Demerits: 

(i) They are expensive. 

(ii) Some of them having branching are non-biodegradable, therefore create water pollution. Detergents are suitable for hard water having Mg²⁺ and Ca²⁺ ions because they do not form insoluble salts with Mg²⁺ and Ca²⁺ ions.

1) General formula for Alkanes : C_n H_2n+2 . 

2) Unsaturated Hydrocarbons in the list are : 

Propene C₃H₆ , Butene C₄H₆ , Pentyne C₅H₈, Hexyne C₆H₁₀. 

3) Homologous series of Alkynes is C₂H₂ (Ethyne), C₃H₄ (Propyne), C₄H₆ (Butyne), C₅H₈ (Pentyne), C₆H₁₀ (Hexyne).

4) Formula of Hexyne is C₆ H₁₀

When any molecule, liku H₂ adds to unsaturated hydrocarbon because of the double and triple bond it is called addition reaction.

CH₂=CH₂+H₂+Ni → C₂H₆

Use - Hydrogenation of vegetable oils. 

Catalyst- Increase the rate of reaction.

Substitution reaction -CH₄Cl₂ → CH₃Cl+HCl one atom is replaced by another ; two products only, one product in addition reaction.

False

Esters are formed as a result of reaction between an alcohol and a carboxylic acid.

i) What is carboxylic acid? 

ii) What is Alcohol?

a) Ester 

b) Alcohol

(b) (i) Metal M which is in the middle of the reactivity series is reduced by aluminium, e.g

3MnO₂(s) + 4Al(s) → 2Al₂O₃(s) + 3Mn(l)

(ii) Metal N will be obtained by electrolytic reduction, e.g. A1 is obtained by electrolytic reduction

Those hydrocarbons in which valency of carbon is satisfied by single bonds only are called sturated hydrocarbons.