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The correct answer is

(D) (iv)

The correct answer is

(D) D

The correct answer is

(D) white

The compound contains 3 carbons. The alkane with 3 carbons is “propane”. There is a –CHO group (aldehyde) in this compound. Hence the name would contain the suffix “- al”.

The IUPAC name would then be:

Propane – ‘e’ + ‘-al’ → Propanal

3          2         1

CH₃ - CH₂ - CHO

There are three carbon atoms in the chain. So, the name of the basic carbon chain is ‘propane’. The functional group present in aldehyde (-CHO). So, the suffix used is ‘al’. The name of the carbon chain is modified by replacing the final ‘e’ with ‘al’. So, the name of the given compound is ‘propanal’.

C) 4 – amino – 3 – hydroxy butanoic acid

(C) displacement reaction

The next homolog of CH₃ CH₂ CHO is CH₃ CH₂ CH₂ CHO (its IUPAC name is butanol). Since homologs differ by – CH₂

B) — COOH >CONH₂ > CHO NH₂ 

A homologous series is a group or a class of organic compounds having the same general formula and similar chemical properties in which the successive members differ by a – CH₂ group.

Characteristics of homologous series:

• All members of a homologous series contain the same elements and functional group.
•  All members of a homologous series can be prepared by a common method. 
• Chemical properties of the members of a homologous series are similar.

To protect the iron articles from corrosion. When iron articles are exposed to moist air, corrosion takes place. When the surface is covered by paint, it is not exposed to moist air.

To flush out any air or oxygen present in the packet. In the absence of oxygen, food items will not get rancid.

C) Butanoic acid

 (i) But-1-ene (ii) Ethanal

Since iron is more reactive than copper, it displaces copper from copper sulphate solution and the blue colour of solution fades. Due to the deposition of copper on iron nail, iron nail become brownish

i. Oil and fat containing food items get oxidised in presence of oxygen and become rancid.
ii. Flushing of these food items with nitrogen avoid their contact with oxygen and inturn prevents rancidity.

1. The larva that emerges from the eggs, known as tadpole, have oval bodies and long, vertically flattened tail and are fully aquatic. 

2. Tadpole lack eyelids and have cartilaginous skeleton. They take respiration through external gills, later it develops internal gills. It looks like a fish at this stage completely. The vertically flattened tails use for swimming. 

3. Tadpole lack true teeth, but the jaws two elongated parallel rows of small structures called keradonts in their upper jaw and three rows of keradonts in the lower jaw as same as the fish has. 

4. Tadpole are typically herbivorous, feeding mostly on algae, including diatoms, filtered the water through the gills. 

5. The tadpoles may be as short as a week during metamorphosis.

B) Buta – 1, 2 – diene

D) Carboxylic acids

(a) Silver sulphide, copper carbonate coating is formed on Ag & Cu article.

(b) Galvanization is a method of protecting steel and iron from rusting by coating them with a thin layer of zinc. The galvanized article is protected against rusting even if the zinc coating is broken.

(c) Alloy is a homogeneous mixture of two or more metals and non-metals. It is prepared by first melting the primary metal and then dissolving the other elements in it in definite proportion. It ii then cooled at room temperature.

(i) On mixing carbons, it becomes hard and strong,

(ii) On mixing Ni and Cr, it becomes hard and does not rust.

They get tarnished by reacting with atmospheric air to form silver sulphide.

Esters are organic compounds (R—COO—R′) formed by a reaction between an alcohol (R′—OH) and an organic acid (R—COOH), 

i.e. carboxylic acid and usually some catalyst with water as a by-product. 

Esters are used to make perfumes and soap. 

They are also used to produce pharmaceutical products, cosmetics, plasticizers and detergents.

C) saponification

1. Esters are usually volatile liquids having sweet or pleasant smell. 

2. They are also said to have fruity smell. 

3. Esters are used in making artificial perfumes. 

4. This is because of the fact that most of the esters have a pleasant smell.

5. Esters are also used as flavouring agents. 

6. This means that esters are used in making artificial flavours and essences used in icecream, sweets and cool drinks. 

7. The alkaline hydrolysis of esters is known as saponification (Soap making). 

8. That’s why we can appreciate the role of esters in everyday life.

The gas liberated is carbon dioxide.

i) Solvents 

ii) Plasticizers

Nitrogen is flushed in bags of potato chips to prevent rancidity.

A) oxidation

It is a combination reaction.

CO ie., carbon monoxide is the reducing agent in the given reaction, as it removes oxygen from Fe₃O₃ and causes its reduction.

i) Iodine 

ii) Alcohol.

C) ‘A’ is correct, but ‘R’ is incorrect.

True

Compounds are pure substances composed of 2 or more elements chemically combined with one another in a fixed proportion. Water, carbon dioxide are examples of compounds.

Hydrocarbons participate in sp² hybridisation is C₂H₄

C) A is incorrect, B is correct.

(a) When iron powder is added to the blue coloured copper sulphate solution, the iron ions formed from iron atoms take the place or Cu²⁺ ions in CuSO₄, and copper atoms, formed from Cu²⁺ ions comes out i.e. the more reactive iron displaces the less reactive Cu from copper sulphate. Therefore this reaction is a displacement reaction.

(b) The reaction in which the place of the ion of a less reactive element in a compound is taken by another more reactive element by formation of its own ions, is called displacement reaction.

Potato chips manufacturers ill the packet of chips with nitrogen gas to prevent the chips from getting oxidized. If the oxidation takes place, the chips can become rancid and their smell and taste will change.

Hence, to prevent oxidation, the packet of chips are filled with nitrogen gas. Nitrogen gas is an antioxidant.

(a Zn + CuSO₄→ ZnSO₄ + Cu 

(b) 2Al + 3H₂O →Al₂O₃ + 3H₂ 

(c) 2Na + 2H₂O → 2NaOH + H₂

i) 1 – Bromo Ethane

ii) Ethanol

iii) 2 – Butanone

iv) 2, 3 – dichloro Butane

C) ‘A’ is correct, but ‘R’ is incorrect.

The type of reaction is displacement reaction

In the given reaction: 

Fe + CuSO₄ (aq) → FeSO₄ (aq) + Cu(s) 

The iron metal being more reactive than copper displaces it, and forms a new compound that is FeSO₄

3Fe(s) + 4H₂O(g) → Fe₃O₄ (s) + 4H₂ (g)

In the above reaction, the iron metal is getting oxidized to Fe₃O₄ by gaining oxygen atoms. H₂O is getting reduced to H₂ by losing oxygen atom. Hence, water is an oxidizing agent as it undergoes reduction.

(a) 3Fe + 4H₂O → Fe₃O₄ + 4H₂

(b) Ca + H₂O → Ca(OH)₂ + H₂

(c) K + H₂O → 2KOH + H₂

C) displacement

C) Zn gets oxidised

Aluminium and copper metals are used for making cooking vessels because they are good conductors of heat and they have high melting points.