datavorous/entrance-exam-dataset huggingface dataset:
Chemosynthetic autotrophic bacteria produce ATP by

Options:
A oxidising various organic substances.
B oxidising various inorganic substances.
C reducing various inorganic substances.
D recycling various organic substances.

The correct answer is:
oxidising various inorganic substances.

Solution:
Chemosynthetic autotrophic bacteria oxidise various inorganic substances such as nitrates, nitrites and ammonia and use the released energy for their ATP production. They play a great role in recycling nutrients like nitrogen, phosphorous, iron and sulphur.

Topic: Biology, Biological Classification, NEET
Chemosynthetic bacteria are those bacteria which

Options:
A do not carry out photosynthesis
B synthesize food without light
C are unable to carry out chemical reactions
D carry out synthesis food in the presence of light

The correct answer is:
synthesize food without light

Solution:
Chemosynthetic bacteria oxides various inorganic substances such as nitrates, nitrites, and ammonia and use the released energy for their ATP production. They play a very important role in recycling nutrients like nitrogen, phosphorus iron and sulphur. These bacteria do not possess photosynthetic pigments. They obtain carbon from organic compounds made by other organisms. They include nitrifying bacteria (Nitrosomes, Nitrobacter), iron bacteria (Ferrobacillus, Leptothrix), hydrogen bacteria, i.e., methanogens (Hydrogenomonas) sulphur bacteria (Thiobacillus, Beggiatoa) and carbon monoxide bacteria (Carboxydomonas).

Topic: Biology, Biological Classification, NEET
Chemosynthetic bacteria are

Options:
A Autotrophic
B Heterotrophic
C Parasitic
D Saprotrophic

The correct answer is:
Autotrophic

Solution:
Chemosynthetic bacteria are autotrophic and make their own food by oxidising inorganic substances.

Topic: Biology, Biological Classification, NEET
Chernobyl and Three Mile Island are related with which of the following.

Options:
A Air pollution
B Water pollution
C Radioactive pollution
D Zinc Mining.

The correct answer is:
Radioactive pollution

Solution:
Initially nuclear energy was hailed as a non polluting way for generating electricity but it has two very serious inherent problems. The first is accidental leakage, as occurred in the Three Mile island and Chernobyl incidents and the second is the safe disposal of radioactive wastes.

Topic: Biology, Environmental Issues, NEET
Chiasmata are most clearly visualised in which stage?

Options:
A Diakinesis
B Diplotene
C Metaphase II
D Pachytene

The correct answer is:
Diplotene

Solution:
The beginning of diplotene is recognised by the dissolution of the synaptonemal complex and the tendency of the recombined homologous chromosomes of the bivalents to separate from each other except at the sites of crossovers. These X-shaped structures are called chiasmata that appear in diplotene stage.

Topic: Biology, Cell Cycle and Cell Division, NEET
Chief pollinators of agricultural crops are

Options:
A Butterflies
B Bees
C Moths
D Beetles

The correct answer is:
Bees

Solution:
The majority of flowering plants use a range of animals as pollinating agents. Bees, butterflies, flies, beetles, wasps, ants, moths, birds (sunbirds and hummingbirds), and bats are the common pollinating agents. Among the animals, insects, particularly bees are the dominant biotic pollinating agents that pollinate about 80% of the total insect-pollinated flowers. Pollination by insects is known as Entomophily.

Topic: Biology, Sexual Reproduction in Flowering Plants, NEET
Child B is born with the palm as depicted in the figure below. Which statement about this child is correct?

Options:
A The child has 47 chromosomes which includes an extra X chromosome
B The has 45 chromosomes which includes one X chromosome less
C The has 45 chromosomes which includes one autosome less
D The child has 47 chromosomes which includes an extra autosome

The correct answer is:
The child has 47 chromosomes which includes an extra autosome

Solution:
Down's Syndrome is caused due to the presence of an additional copy of the chromosome number 21 (trisomy of 21). This disorder was first described by Langdon Down (1866). The affected individual is short statured with small round head, furrowed tongue and partially open mouth. Palm is broad with characteristic palm crease (simian crease). Physical, psychomotor and mental development is retarded.

Topic: Biology, Principles of Inheritance and Variation, NEET
Child death may occur in the marriage between:

Options:
A Rh+ man and Rh+ woman
B Rh+ man and Rhâ woman
C Rh– man and Rh– woman
D Rh– man and Rh+ woman

The correct answer is:
Rh+ man and Rh– woman

Solution:
Rh factor was discovered by Karl Landsteiner. A child of Rh+ man will be Rh+ whether the mother is Rh+ or Rhâ so, when the blood of Rh + child (in the womb) mixes with the blood of Rhâ mother, then some antibodies in motherâs blood may cause death of the child. If the birth takes place then there is a possibility of child death in the early years. This in known as erythroblastosis foetalis. In most cases the Ist pregnancy may succeed but the chances of successful successive pregnancies decrease many folds.

Topic: Biology, Body Fluids and Circulation, NEET
"Chile saltpetre" is an ore of

Options:
A Iodine
B Sodium
C Bromine
D Magnesium

The correct answer is:
Sodium

Solution:
Sodium nitrate is NaNO3. It's salt is known as Chile saltpetre or Peru saltpetre(due to large deposits found in the Atacama desert in these countries).

Topic: Chemistry, General Principles and Processes of Isolation of Metals, NEET
Chilled ethyl alcohol is used during rDNA technology for

Options:
A Precipitation of histones
B Precipitation of DNA
C Removal of enzymes
D Precipitation of cell fragments.

The correct answer is:
Precipitation of DNA

Solution:
In the process of Recombinant DNA technology the first step is isolation of the genetic material. In order to cut the DNA with the help of restruiction enzymes the DNA has to be in a pure form and should be free from other macromolecules. For the release of DNA with other macromolecules like RNA, proteins, polysaccharides and also lipids the cell needs to break open. This is achieved by treating the cell with enzymes like lysozymes, cellulose, etc. The RNA is removed by ribonuclease and proteins by proteases. Similarly other macromolecules are removed by appropriate enzymes and finally DNA can be precipitated out as a collection of fine threads in the suspension after adding chilled ethyl alcohol.

Topic: Biology, Biotechnology - Principles and Processes, NEET
Chipko movement in which local women showed enormous bravery in protecting trees by hugging them occurred in

Options:
A 1731 in Jodhpur led by Amrita Devi Bishnoi
B 1974 in Garhwal Himalayas led by Gaura Devi
C 1983 in Uttara Kannada led by Pandurang Hegde
D 1985 in Maharashtra led by Medha Patkar

The correct answer is:
1974 in Garhwal Himalayas led by Gaura Devi

Solution:
In 1731 Amrita Devi Bishnoi sacrificed her life for protecting trees in Jodhpur. Chipko movement in which local women showed enormous bravery in protecting trees by hugging them occurred in 1974 in Garhwal Himalayas led by Gaura Devi. Appiko movement is the southern version of the Chipko movement. It occurred in 1983 in Uttara Kannada led by Pandurang Hegde. Narmada Bachao Andolan started in 1985 in Maharashtra/ Gujarat led by Medha Patkar to reduce the proposed height of Sardar Sarovar dam from 130 to 88 m.

Topic: Biology, Environmental Issues, NEET
Chipko movement was launched for the protection of

Options:
A grasslands
B forests
C livestock
D wet lands

The correct answer is:
forests

Solution:
In 1973, the Chipko Movement (Chipko means to hug or stick to) was launched by Chandi Prashad Bhatt and Sunder Lal Bahuguna against large scale felling of trees by timber contractors in the Uttarakhand hills. The starting point was Chamoli district of Garhwal region in Uttarakhand.

Topic: Biology, Biodiversity and its Conservation, NEET, NEET 2009 (Screening)
Chipko movement was launched for the protection of

Options:
A Forests
B Livestock
C Wetlands
D Grasslands

The correct answer is:
Forests

Solution:
Chipko movement was launched for the protection of forests. The Chipko movement refers to the unique form of protest adopted by the rural people in the Himalayan region of India in the 1970s and 80s, against the indiscriminate logging and felling of trees that spelt the destruction of their environment. The first Chipko action occurred in April 1973. Over the next five years,the movement spread to several hill districts in Uttar Pradesh. In 1980, Chipko activists won a fifteen-year ban on green felling in the Himalayan forests.

Topic: Biology, Environmental Issues, NEET
Chlamydomonas and Chlorella were categorized under which kingdom in the five-kingdom classification?

Options:
A Fungi
B Protozoa
C Protista
D Monera

The correct answer is:
Protista

Solution:
Chlamydomonas and Chlorella, both can be categorized under the kingdom Protista, as they both follow the definition of a Protista, i.e., they are unicellular eukaryotes.

Topic: Biology, Biological Classification, NEET
Chloramine-T is used as

Options:
A Disinfectant
B Antipyretic
C Analgesic
D Antiseptic

The correct answer is:
Antipyretic

Solution:
Antiseptic drugs causes destruction of micro-organism that produce septic disease e.g.
Dettol, Savlon acriflavin, Boric acid, Phenol Iodoform, KMnO4 and some dyes such as Chloramine T, methylene blue.

Topic: Chemistry, Chemistry in Everyday Life, NEET
Chlorenchyma is known to develop in the:

Options:
A cytoplasm of Chlorella
B mycelium of a green mould such as Aspergillus
C spore capsule of a moss
D pollen tube of Pinus

The correct answer is:
spore capsule of a moss

Solution:
The apophysis of moss capsule contains chloroplast bearing parenchymatous cells, called as chlorenchyma or assimilatory parenchyma, but to the presence of chloroplasts, chlorenchyma cells have the ability to prepare food by the process of photosynthesis.
Related Theory
Chlorenchyma cells carryout photosynthesis and manufacture food.

Topic: Biology, Plant Kingdom, NEET, NEET 2003
Chlorination of benzene in the presence of halogen carrier is an example of

Options:
A Aromatic electrophilic substitution
B Aromatic nucleophilic substitution
C Aromatic electrophilic addition
D Aromatic nucleophilic addition

The correct answer is:
Aromatic electrophilic substitution

Solution:
Chlorination of benzene in the presence of halogen carrier is an example of Aromatic electrophilic substitution.
Mechanism of chlorination in brief can be given as follows
Cl–Cl+FeCl3(halogencarrier)→Cl++FeCl4-(electrophile)

FeCl4-→H+FeCl3+HCl

Topic: Chemistry, Hydrocarbons, NEET
Chlorination of methane does not occur in dark because

Options:
A methane can form free radicals in presence of sunlight only
B to get chlorine free radicals from Cl2 molecules energy is required. It cannot happen in dark
C substitution reaction can take place only in sunlight and not in dark
D termination step cannot take place in dark. It requires sunlight

The correct answer is:
to get chlorine free radicals from Cl2 molecules energy is required. It cannot happen in dark

Solution:
Chlorination of methane is free radical substitution. to get chlorine free radical energy is required which is provided by sunlight to initiate the reaction.
Cl2→hvCl⋅+Cl⋅

Topic: Chemistry, Hydrocarbons, NEET
Chlorination of toluene in presence of light and heat followed by treatment with aqueous aq. KOH gives ( Cl 2 is in excess)

Options:
A m-Cresol
B p-Cresol
C 2, 4-Dihydroxytoluene
D Benzoic acid

The correct answer is:
Benzoic acid

Solution:
Here benzoic acid is formed as follows

Topic: Chemistry, Haloalkanes and Haloarenes, NEET
Chlorine gas is passed into a solution containing KF, KI and KBr and CHCl3 is added. The initial colour in CHCl3 layer is

Options:
A Violet due to formation of I2
B Orange due to formation of Br2
C Colourless due to formation of F2
D No colour change due to no reaction

The correct answer is:
Violet due to formation of I2

Solution:
Cl2+2KI→2KCl+I2
Iodine will be liberated first to impart violet colour to CHCl3 layer.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
Chlorine is commonly used in the paper and rayon manufacturing industry. What is its role in the bleaching process for woodpulp and textiles?

Options:
A It strengthens the fibers.
B It softens the material.
C It enhances the texture.
D It oxidizes and removes color from the material.

The correct answer is:
It oxidizes and removes color from the material.

Solution:
Chlorine's role in the bleaching process for woodpulp and textiles is to oxidize and remove color from the material, making it suitable for various applications.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
Chlorine is prepared in the laboratory by treating manganese dioxide (MnO2) with aqueous hydrochloric acid according to the reaction: 4HCl (aq) + MnO2(s) → 2H2O(l) + MnCl2(aq) + Cl2(g) How many grams of HCl react with 5.0 g of manganese dioxide?

Options:
A 8.39g HCl
B 9.45g HCl
C 7.87g HCl
D 8.95g HCl

The correct answer is:
8.39g HCl

Solution:
Correct Option is : (A)
8.39g HCl

Topic: Chemistry, Some Basic Concepts of Chemistry, NEET
Chlorine is used for the bleaching of woodpulp and textiles. Why is chlorine effective in bleaching?

Options:
A It enhances the color of the material.
B It removes microorganisms.
C It oxidizes and breaks down colored substances.
D It improves the texture of the material.

The correct answer is:
It oxidizes and breaks down colored substances.

Solution:
Chlorine is effective in bleaching because it oxidizes and breaks down colored substances, making them colorless.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
Chlorine is used in the manufacture of various organic compounds. Which of the following compounds is NOT listed in the paragraph as being manufactured using chlorine?

Options:
A CCl4
B CHCl3
C DDT
D H2O

The correct answer is:
H2O

Solution:
The paragraph mentions that chlorine is used in the manufacture of organic compounds such as CCl4, CHCl3, and DDT. Water (H2O) is not mentioned as a compound manufactured using chlorine.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
Chlorine is used to purify drinking water. Excess of chlorine is harmful. The excess of chlorine is removed by treating with sulphur dioxide. Present a balanced equation for this redox change taking place in water.

Options:
A $\mathrm{Cl}_2(g)+\mathrm{SO}_2(g)+2 \mathrm{H}_2 \mathrm{O}(l) \rightarrow 2 \mathrm{HCl}(a q)+\mathrm{H}_2 \mathrm{SO}_4(a q)$
B $\mathrm{Cl}_2(g)+2 \mathrm{SO}_2(g)+2 \mathrm{H}_2 \mathrm{O}(l) \rightarrow 2 \mathrm{HCl}(a q)+\mathrm{H}_2 \mathrm{SO}_4(a q)$
C $\mathrm{Cl}_2(g)+\mathrm{SO}_2(g)+2 \mathrm{H}_2 \mathrm{O}(l) \rightarrow 2 \mathrm{HCl}(a q)+\mathrm{H}_2 \mathrm{SO}_3(a q)$
D $\mathrm{Cl}_2(g)+2 \mathrm{SO}_2(g)+2 \mathrm{H}_2 \mathrm{O}(l) \rightarrow 2 \mathrm{HCl}(a q)+\mathrm{H}_2 \mathrm{SO}_3(a q)$

The correct answer is:
$\mathrm{Cl}_2(g)+\mathrm{SO}_2(g)+2 \mathrm{H}_2 \mathrm{O}(l) \rightarrow 2 \mathrm{HCl}(a q)+\mathrm{H}_2 \mathrm{SO}_4(a q)$

Solution:
Correct Option is : (A)
$\mathrm{Cl}_2(g)+\mathrm{SO}_2(g)+2 \mathrm{H}_2 \mathrm{O}(l) \rightarrow 2 \mathrm{HCl}(a q)+\mathrm{H}_2 \mathrm{SO}_4(a q)$

Topic: Chemistry, Redox Reactions, NEET
Chlorine reacts with hot and concentrated NaOH and produces compounds (X) and (Y). Compound (X) gives white precipitate with silver nitrate solution. The average bond order between Cl and O atoms in (Y) is ______ .

Options:
A 1.67
B 0.835
C 2.67
D 2

The correct answer is:
1.67

Solution:
3Cl2+6NaOHâ5NaCl+NaClO3+3H2O
NaCl+AgNO3âAgClWhite ppt+NaNO3
Y is NaClO3âClO3-
Bond order =1+ÏÏ
=1+23=53=1.67

Topic: Chemistry, Chemical Bonding and Molecular Structure, NEET
Chlorine reacts with hydrogen to form which compound?

Options:
A H2O
B NaCl
C HCl
D Ca(OCl)2

The correct answer is:
HCl

Solution:
Chlorine reacts with hydrogen to form hydrogen chloride, which is represented by the chemical formula HCl.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
Chlorobenzene reacts with trichloro acetaldehyde in the presence of H2SO4

The major product formed is :

Options:
A
B
C
D

The correct answer is:

Solution:

Topic: Chemistry, Aldehydes and Ketones, NEET
Chloroform, when kept open, is oxidised to

Options:
A CO2
B COCl2
C CO2 , Cl2
D None of these

The correct answer is:
COCl2

Solution:
Chloroform is oxidised to a poisonous gas, phosgene (COCl2) by atmospheric oxidation.
CHCl3 + O → COCl2+HCl

Topic: Chemistry, Haloalkanes and Haloarenes, NEET
'Chlorophyll a' is absent in which of the following photosynthetic organism?

Options:
A Cyanobacteria
B Red algae
C Brown algae
D Bacteria

The correct answer is:
Bacteria

Solution:
The photosynthetic bacteria use inorganic electron donors such as H2S, H2, sulphur compound, etc. They contain bacterio-chlorophyll but chlorophyll a is absent.

Topic: Biology, Photosynthesis in Higher Plants, NEET
Chlorophyll in chloroplasts is located in:

Options:
A grana
B pyrenoid
C stroma
D both grana and stroma.

The correct answer is:
grana

Solution:
The green pigment chlorophyll is located within the thylakoid membrane in the grana. The space between the thylakoid and the chloroplast membranes is called the stroma (Ref. to Fig.)
Related Theory
Chlorophyll is found in virtually all photosynthetic organisms, including green plants, cyanobacteria, and algae. It absorbs energy from light; this energy is then used to convert carbon dioxide to carbohydrates. Chlorophyll is a pigment found in green plants.

Topic: Biology, Cell - The Unit of Life, NEET, NEET 2005
Chlorophyll is

Options:
A Soluble in organic solvents
B Soluble in water
C Soluble in both organic solvents and water
D None of the above

The correct answer is:
Soluble in organic solvents

Solution:
Chlorophyll is soluble in organic solvents like alcohol, acetone, etc.

Topic: Biology, Photosynthesis in Higher Plants, NEET
Chlorophyll present in green leaves of plants absorbs light at 4.620 × 1014Hz. Calculate the wavelength of radiation in nanometers. Which part of the electromagnetic spectrum does it belong to?

Options:
A Wavelength = 6.49 nm, Ultraviolet region
B Wavelength = 649 nm, Infrared region
C Wavelength = 649 nm, Visible region
D Wavelength = 6.49 nm, Infrared region

The correct answer is:
Wavelength = 649 nm, Visible region

Solution:
Correct Option is : (C)
Wavelength = 649 nm, Visible region

Topic: Chemistry, Structure of Atom, NEET
Chlorophyll, the green colouring matter of plants responsible for photosynthesis, contains 2.68% of magnesium by mass. Calculate the number of magnesium atoms in 2.00 g of chlorophyll.

Options:
A 1.345×1023 atoms of Mg
B 1.345×1028 atoms of Mg
C 1.345×1022 atoms of Mg
D 1.345×1021 atoms of Mg

The correct answer is:
1.345×1021 atoms of Mg

Solution:
100 g chlorophyll contains 2.68 g Mg=2.6824 mole Mg
2 g chlorophyll contains 2.68×224×100 mole Mg= 2.2 × 10-3 mole Mg
No. of Mg atoms = 2.2 ×10-3 × 6.023 ×1023
=1.345×1021 atoms of Mg

Topic: Chemistry, Some Basic Concepts of Chemistry, NEET
Chloropicrin is obtained by the reaction

Options:
A steam on carbon tetrachloride
B nitric acid on chlorobenzene
C chlorine on picric acid
D nitric acid on chloroform

The correct answer is:
nitric acid on chloroform

Solution:
Chloropicrin is prepared by heating chloroform with concentrated nitric acid.
$$
\mathrm{CHCl}_3+\mathrm{HONO}_2 \rightarrow \mathrm{CNO}_2^{-} \mathrm{Cl}_3+\mathrm{H}_2 \mathrm{O}
$$
chloropicrin
Related Theory
Chloropicrin (Trichlara(nitro)methane) is also prepared by the reaction of nitromethane with sodium hypochlorite.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET, NEET 2004
Chloroplast of Chlamydomonas is

Options:
A Collar–shaped
B Spiral
C Cup-shaped
D

Stellate

The correct answer is:
Cup-shaped

Solution:
Shape and number of chloroplast in a different member of algae is different.
Chlamydomonas – cup-shaped, 1/cell
Zygnema – Stellate, 2 /cell
Spirogyra – Spiral, 1/cell
Ulothrix – Collar shaped, 1/cell

Topic: Biology, Plant Kingdom, NEET
Chlorosis is caused due to the deficiency of

Options:
A Magnesium
B Calcium
C Boron
D Copper

The correct answer is:
Magnesium

Solution:
Magnesium is a component of chlorophyll and an important binding substance for ribosomal sub-units. Its deficiency causes inter-veinal chlorosis, development of anthocyanin and depression of internal phloem.

Topic: Biology, Mineral Nutrition, NEET
Cholecystokinin acts on

Options:
A pancreas only
B gall bladder only
C pancreas and gall bladder
D pituitary gland only

The correct answer is:
pancreas and gall bladder

Solution:
Cholecystokinin acts on the pancreas to release pancreatic enzymes and on the gall bladder to release bile juice.

Topic: Biology, Digestion and Absorption, NEET
Cholera is caused by

Options:
A Virus
B Bacteria
C Fungi
D Protozoan

The correct answer is:
Bacteria

Solution:
A bacteria Vibrio cholerae causes cholera. Cholera is an infectious disease that causes severe watery diarrhoea, which can lead to dehydration and even death if untreated. It is caused by eating food or drinking water contaminated with a bacterium called Vibrio cholerae.

Topic: Biology, Human Health and Diseases, NEET
Chondrichthyes is characterized by

Options:
A placoid scale and terminal mouth.
B ctenoid scale and terminal mouth.
C ctenoid scale and ventral mouth.
D placoid scale and ventral mouth.

The correct answer is:
placoid scale and ventral mouth.

Solution:
Chondrichthyes is a class which belongs to subphylum Vertebrata of phylum Chordata. This class comprises of cartilaginous fishes. These fishes show the presence of a ventrally located mouth. The skin of these fishes is covered by minute placoid scales.
Ctenoid scales and terminal mouth is present in class Osteichthyes.

Topic: Biology, Animal Kingdom, NEET
Choose a saturated fatty acid from the following compounds.

Options:
A Palmitic acid
B Linoleic acid
C Oleic acid
D Arachidonic acid

The correct answer is:
Palmitic acid

Solution:
Palmitic acid, or hexadecanoic acid in IUPAC nomenclature, is the most common saturated fatty acid found in animals, plants and microorganisms. Its chemical formula is CH3CH214COOH .

Topic: Chemistry, Biomolecules, NEET
Choose CORRECT statements from the following.

(P) The Western Ghats have greater amphibian species diversity than the Eastern Ghats

(Q) Diversity exists at all levels of biological organization ranging from macromolecules within cells to biomes.

(R) Rauwolfia vomitoria show the genetic variation in terms of potency and concentration of the reserpine produced.

(S) Norway has a greater ecosystem diversity than India.

Options:
A P and Q only
B Q and S only
C P, Q and R only
D S only

The correct answer is:
P, Q and R only

Solution:
Socio-biologist Edward Wilson gave the term biodiversity to the combined diversity which is seen at the different levels of biosphere, where we find heterogeneity not only at species level but also at the level of macromolecules within cells. There are three different types of biodiversity patterns seen most commonly - genetic, species and ecological. Rauwolfia vomitoria growing in different regions of Himalayas has different potency and concentration of reserpine. This is an example of genetic diversity. When we compare the Eastern and Western Ghats we find that more species variations at the Western Ghats, this is species diversity. Ecological diversity can been seen in terms that the India has more ecosystem diversity than Norway due to the presence of deserts, rain forests, wetlands, etc.

Topic: Biology, Biodiversity and its Conservation, NEET
Choose from the indicated protons, the one that is most acidic

Options:
A 1
B 2
C 3
D 4

The correct answer is:
4

Solution:
Deprotonation of hydrogen labelled 4 produces a conjugate base which has more stable resonating structure and a resonance structure in which negative charge is present on the electronegative oxygen atom. Therefore, hydrogen labelled 4 is most acidic.

Topic: Chemistry, General Organic Chemistry, NEET