datavorous/entrance-exam-dataset huggingface dataset:
Which of the following is an incorrect set of quantum members?

Options:
A n=2, l=0, m=0
B n=1, l=0, m=0
C n=3, l=3, m=0
D n=2, l=1, m=1

The correct answer is:
n=3, l=3, m=0

Solution:
Maximum l value should be equal to n−1 and it cannot be equal to n.

∵ for (l) It can be upto (n-1) and

Thus, m=±l i.e. +l,0,-l

for (a) n=2,l=0,m=0 (correct),

for (b) n=1,l=0,m=0 (correct),

(c) n=3,l=3 (not correct),

(d) n=2,l=1,m=1 (correct),

Topic: Chemistry, Structure of Atom, JEE Main
Which of the following is an incorrect statement?

Options:
A Homo erectus live on Earth round 1.5 - 1.7 million years ago
B Homo sapiens appeared in African grassland
C Archaeopteryx had characters of birds and reptiles.
D All the Darwin finches were discovered on a single island of Galapagos.

The correct answer is:
All the Darwin finches were discovered on a single island of Galapagos.

Solution:
Darwin's finches, named due to their role in Charles Darwin's theories on evolution. The evolution of Darwin's finches on the Galapagos Islands is a classic example of species formation and illustrates how adaptation to local conditions produces the divergence that is the heart of species formation: i.e. such an evolutionary process, giving rise to new species adapted to new habitats and ways of life, is called adaptive radiation or divergent evolution. Fascinated with diversity found among the thirteen species and the speed with which they evolved from a common ancestor to adapt to the varied supply of food available on individual islands, Darwin discovered that these adaptations mainly showed up in the shape and size of beaks. Darwin's finches comprised a group of 15 species. Among them 14 species were endemic to the Galapagos island and 1 species was from Cocos Islands in the Pacific ocean.

Topic: Biology, Evolution, NEET
Which of the following is an incorrect statement?

Options:
A Darwin finches show convergent evolution.
B Homo erectus evolved earlier than Homo sapiens.
C Homo sapiens appeared in African grassland
D Archaeopteryx is connecting link between the birds and reptiles.

The correct answer is:
Darwin finches show convergent evolution.

Solution:
Darwin's finches, named due to their role in Charles Darwin's theories on evolution, are the most renowned land birds of the Galapagos. Fascinated with diversity found among the thirteen species and the speed with which they evolved from a common ancestor to adapt to the varied supply of food available on individual islands, Darwin discovered that these adaptations mainly showed up in the shape and size of beaks.

Topic: Biology, Evolution, NEET
Which of the following is an incorrect statement about cannabinoids?

Options:
A Cannabinoids are the group of chemicals that interact with cannabinoids receptors present mainly in the brain and gastrointestinal tract.
B Cannabinoids are naturally obtained from the inflorescence of the Cannabis sativa plant.
C Cannabinoids includes marijuana, hashish, charas and ganja.
D Cannabinoids are generally taken by inhalation and oral ingestion, which affects the cardiovascular system of the body.

The correct answer is:
Cannabinoids are the group of chemicals that interact with cannabinoids receptors present mainly in the brain and gastrointestinal tract.

Solution:
Cannabinoids are a group of chemicals that interact with cannabinoids receptors present mainly in the brain. They belong to hallucinogenic drugs, which often make users 'see the sound and hear light'. They are obtained from different parts of Cannabis sativa plants.

Topic: Biology, Human Health and Diseases, NEET
Which of the following is an incorrect statement about the second response of the body against a previously infected antigen?

Options:
A The main antibody formed during the secondary response against a previously encountered antigen is IgM.
B The secondary immune response of the body is based on memory cells.
C The immune response against a previously infected antigen is also known as anamnestic response.
D The secondary immune response gives effective immunity.

The correct answer is:
The main antibody formed during the secondary response against a previously encountered antigen is IgM.

Solution:
Acquired immunity is pathogen-specific. It is characterised by memory. This means when our body encounters a pathogen for the first time it produces a response called primary response which is of low intensity. Subsequent encounter with the same pathogen elicits a highly intensified secondary or anamnestic response. This is ascribed to the fact that our body appears to have memory of the first encounter. The primary and secondary immune responses are carried out with the help of two special types of lymphocytes present in our blood, i.e., B-lymphocytes and T-lymphocytes.

The B-lymphocytes produce an army of proteins in response to pathogens into our blood to fight with them. These proteins are called antibodies. The T-cells themselves do not secrete antibodies but help B-cells to produce them. Different types of antibodies are produced in our body. IgA, IgM, IgE and IgG are some of them. Though IgG is the most common antibody formed by the memory cells, IgA- and IgE-expressing B-cells play an important role in the secondary immune response.

Topic: Biology, Human Health and Diseases, NEET
Which of the following is an incorrect statement regarding benign tumor?

Options:
A Remain confined to their original location
B The do not spread to other parts
C These cells grow very rapidly
D They cause little damage

The correct answer is:
These cells grow very rapidly

Solution:
Benign tumors generally have a slower growth rate than malignant tumors and the tumor cells are usually more differentiated .

Topic: Biology, Human Health and Diseases, NEET
Which of the following is an intensive property of the system?

Options:
A Density
B Volume
C Total heat capacity
D Mass

The correct answer is:
Density

Solution:
Intensive properties are those that depend upon the nature of the substance.
The ratio of two extensive properties is an intensive property.

Topic: Chemistry, Thermodynamics (C), JEE Main
Which of the following is an intensive property?

Options:
A Volume
B Enthalpy
C Surface tension
D Free energy

The correct answer is:
Surface tension

Solution:
The properties, which do not depend on the amount of substance, are called intensive property. e.g., surface tension, viscosity etc.

Topic: Chemistry, Thermodynamics (C), JEE Main
Which of the following is an intrinsic semiconductor?

Options:
A Germanium
B Bismuth
C Boron
D Antimony

The correct answer is:
Germanium

Solution:
Concept:
- Intrinsic Semiconductors:
- A pure semiconductor is called an intrinsic semiconductor. It has thermally generated current carriers.
- They have four electrons in the outermost orbit of atoms and atoms are held together by a covalent bond.
- Fermi energy level lies at the center of the conduction band ( $C, B$ ) and valence band (V.B) in an intrinsic semiconductor.
- Because of fewer charge carriers at room temperature, intrinsic semiconductors have low conductivity so they have no practical use.
- An ideal, perfectly pure semiconductor (with no impurities) is called an intrinsic semiconductor.
- In an intrinsic semiconductor, the number of free electrons in the conduction band is equal to the number of holes in the valence band.
- The current caused by electrons and holes is equal in magnitude.
- The total current in an intrinsic semiconductor is the sum of hole and electron current.
- Total current = Electron current + Hole current

Topic: Physics, Semiconductors, JEE Main
Which of the following is best close to an ideal black body?

Options:
A Black lamp
B Cavity maintained at constant temperature
C Platinum black
D A lamp of charcoal heated to high temperature

The correct answer is:
Cavity maintained at constant temperature

Solution:
An ideal black body is one which absorbs all the incident radiation without reflecting or transmitting any part of it. Black lamp absorbs approximately \(96 \%\) of incident radiation.

An ideal black body can be realized in practice by a small hole in the wall of a hollow body (as shown in figure) which is at uniform temperature. Any radiation entering the hollow body through the holes suffers a number of reflections and ultimately gets completely absorbed. This can be facilitated by coating the interior surface with black so that about \(96 \%\) of the radiation is absorbed at each reflection. The portion of the interior surface opposite lo the hole is made conical to avoid the escape of reflected ray after one reflection.

Topic: Physics, Thermal Properties of Matter, JEE Main
Which of the following is best close to an ideal black body?

Options:
A Black lamp
B Cavity maintained at constant temperature
C Platinum black
D A lamp of charcoal heated to high temperature

The correct answer is:
Cavity maintained at constant temperature

Solution:
An ideal black body is one which absorbs all the incident radiation without reflecting or transmitting any part of it. Black lamp absorbs approximately \(96 \%\) of incident radiation.

An ideal black body can be realized in practice by a small hole in the wall of a hollow body (as shown in figure) which is at uniform temperature. Any radiation entering the hollow body through the holes suffers a number of reflections and ultimately gets completely absorbed. This can be facilitated by coating the interior surface with black so that about \(96 \%\) of the radiation is absorbed at each reflection. The portion of the interior surface opposite lo the hole is made conical to avoid the escape of reflected ray after one reflection.

Topic: Physics, Thermal Properties of Matter, NEET, NEET 2002
Which of the following is coloured compound?

Options:
A CuF2
B CuI
C NaCl
D MgCl2

The correct answer is:
CuF2

Solution:
The d -block elements form coloured compounds. These compounds have ions with unpaired electron in d-subshell.
i) Na and Mg belong to s-block , so NaCl and MgCl2 are colourless compounds.
ii) CuF2
Oxidation state of Cu in CuF2 is +2
Cu2+=1s2,2s2,2p6,3s2,3p6,4s0,3d9
â´ CuF2 in which Cu has one unpaired electron is coloured.
iii ) CuI
Oxidation state of Cu in CuI =+1
Cu+=1s2,2s2,2p6,3s2,3p6,4s0,3d10
It has no unpaired electron. So, CuI is colourless.
â´ Only CuF2 is coloured among given choices.

Topic: Chemistry, d and f Block Elements, JEE Main
Which of the following is considered a living fossil?

Options:
A Locusta
B Dentalium
C Limulus
D Ascidia

The correct answer is:
Limulus

Solution:
A living fossil is an organism (such as a horseshoe crab, king crab, Tuatara, Coelcanth or a ginkgo tree) that has remained essentially unchanged from earlier geologic times and whose close relatives are usually extinct. Limulus is commonly called king crab.

Topic: Biology, Animal Kingdom, NEET
Which of the following is considered a man-made ecosystem?

Options:
A Estuary
B Crop land
C Grassland
D Desert

The correct answer is:
Crop land

Solution:
TYPES OF ECOSYSTEM:
Ecosystem varies greatly in size from a small pond to a large forest or a sea. Many ecologies regard the entire biosphere as a global ecosystem as a composite of all local ecosystem on earth. Since this system is too much big and complex to be studied at one time, so to make the study easier, it is broadly divided into two basic categories.
i) Terrestrial Ecosystem: It occurs over land e.g., forest, grassland, desert.
ii) Aquatic Ecosystem: It occurs in water bodies e.g., pond, lake, river (freshwater), wetland, sea, estuaries (salt water).
Similarly, w.r.t. human interference the ecosystems are of two types:
i) Natural ecosystem: It develops in nature without human support or interference e.g., forests, marine ecosystem.
ii) Anthropogenic ecosystem or man-made ecosystem: It is the one which is created and maintained by human beings e.g., crop fields, garden, aquarium, Agro ecosystem or agriculture is the largest manmade ecosystem.

Topic: Biology, Ecosystem, NEET
Which of the following is converted into an alcohol on treatment with $\mathrm{HNO}_2$

Options:
A Methyl amine
B Aniline
C Dimethyl amine
D Triethylamine

The correct answer is:
Methyl amine

Solution:

Topic: Chemistry, Amines, JEE Main
Which of the following is corrcet regarding the ecosystem?

Options:
A There is cyclic exchange of materials between living beings and environment.
B The flow of energy is unidirectional.
C It is a self-regulating unit.
D All of these

The correct answer is:
All of these

Solution:
The ecosystem is defined as a system consists of a living community of plants, animals, and microbes together with their physical environment of air, water, soil, etc.

An ecosystem maintains a functional balance amongst its various components. This phenomenon is called homeostasis. The homeostasis or balance of nature is maintained through some control systems like carrying capacity of the ecosystem, the capacity of an ecosystem to recycle the wastes, feedback system, etc.

A functioning ecosystem exhibits biological and chemical activities, rates of plant production, the flow of energy, carbon storage, and nutrient cycling that are characteristic of most forests.

The energy flow in an ecosystem is said to be unidirectional because 90% of the energy gets used up by the organism in a trophic level and is released as heat, and only 10% of the energy is available to be transferred to next trophic level.

Topic: Biology, Ecosystem, NEET
Which of the following is correct?

Options:
A a liquid with low vapour pressure will have a low surface tension and high boiling point
B a liquid with high vapour pressure will have high intermolecular forces and high boiling point
C a liquid with low vapour pressure will have high surface tension and high boiling point
D a liquid with low vapour pressure will have low surface tension and low boiling point

The correct answer is:
a liquid with low vapour pressure will have high surface tension and high boiling point

Solution:
A liquid with low vapour pressure (less volatile) will have a high surface tension and high boiling point.

Topic: Chemistry, Solutions, JEE Main
Which of the following is correct?

Options:
A Vinyl chloride is more reactive than ethyl chloride in SN2
B Vinyl chloride is more reactive than ethyl chloride in SN1
C allyl chloride is less reactive than n-propyl chloride in SN1
D allyl chloride is more reactive than n-propyl chloride in SN2

The correct answer is:
allyl chloride is more reactive than n-propyl chloride in SN2

Solution:
As the electronegativity order of hybridized carbons is sp>sp2>sp3 so in an allylic halide, such as CH2=CH-CH2-Cl, the alpha carbon is much more partially positive than the alpha carbon in(n-propyl chloride) CH 3 − CH 2 − CH 2 −Cl. Therefore, the attacking nucleophile will be attracted to the alpha carbon more in the allylic halide compound than in the primary halide. It means allylic halides tend to follow SN2 pathways more than primary halides.

Topic: Chemistry, Haloalkanes and Haloarenes, JEE Main
Which of the following is correct?

Options:
A \( K_{p} \) will always have some unit.
B \( \mathrm{K}_{\mathrm{c}} \) will always have some unit.
C \( \mathrm{K}_{\mathrm{X}} \) will never have any unit.
D When \( \Delta \mathrm{n}=1, \mathrm{~K}_{\mathrm{p}}=\mathrm{K}_{\mathrm{c}}=\mathrm{K}_{\mathrm{X}} \) then all the three Ks have the same unit.

The correct answer is:
\( \mathrm{K}_{\mathrm{X}} \) will never have any unit.

Solution:
The relation between the various equilibrium constants are,

Kp=KcRT∆n=KxP∆n.

As we know that, Kp and Kc have units of pressure and concentration and as we see from the above relation that the whole equation depends upon the ∆n which is equal to the difference between the number of gaseous product moles and the number of gaseous reactant moles.

Topic: Chemistry, Chemical Equilibrium, JEE Main
Which of the following is correct ?

Options:
A \(\begin{array}{|l|l|l|l|} \hline \begin{array}{l} \text { Crystal } \\ \text { system } \end{array} & \begin{array}{l} \text { Axial } \\ \text { distance } \end{array} & \begin{array}{l} \text { Axial } \\ \text { angles } \end{array} & \text { Examples } \\ \hline \text{Cubic} & a \neq b=c & \alpha=\beta \neq \gamma & \mathrm{Cu}, \mathrm{KCl} \\ & & =90^{\circ} \\ \hline \end{array}\)
B \(\begin{array}{|l|l|l|l|} \hline \begin{array}{l} \text { Crystal } \\ \text { system } \end{array} & \begin{array}{l} \text { Axial } \\ \text { distance } \end{array} & \begin{array}{l} \text { Axial } \\ \text { angles } \end{array} & \text { Examples } \\ \hline \text { Monoclinic } & a \neq b=c & \alpha=\beta=\gamma & \mathrm{PbCrO}_2 \text {, } \\ & =90^{\circ} & \mathrm{PbCrO}_4 \\ \hline \end{array}\)
C \(\begin{array}{|l|l|l|l|} \hline \begin{array}{l} \text { Crystal } \\ \text { system } \end{array} & \begin{array}{l} \text { Axial } \\ \text { distance } \end{array} & \begin{array}{l} \text { Axial } \\ \text { angles } \end{array} & \text { Examples } \\ \hline \text{Rhombohe} & a=b=c & \alpha=\beta=\gamma & \mathrm{CaCO}_3 \\ \text{dral} & & \neq 90^\circ & \mathrm{HgS} \\ \hline \end{array}\)
D \(\begin{array}{|l|l|l|l|} \hline \begin{array}{l} \text { Crystal } \\ \text { system } \end{array} & \begin{array}{l} \text { Axial } \\ \text { distance } \end{array} & \begin{array}{l} \text { Axial } \\ \text { angles } \end{array} & \text { Examples } \\ \hline \text{Triclinic} & a=b=c & a \neq \beta=Y & \mathrm{K}_2 \mathrm{Cr}_2 \mathrm{O}_7 \\ & & \neq 90^{\circ} & \mathrm{CuSO}_4 \\ & & & 5 \mathrm{H}_2 \mathrm{O} \\ \hline \end{array}\)

The correct answer is:
\(\begin{array}{|l|l|l|l|} \hline \begin{array}{l} \text { Crystal } \\ \text { system } \end{array} & \begin{array}{l} \text { Axial } \\ \text { distance } \end{array} & \begin{array}{l} \text { Axial } \\ \text { angles } \end{array} & \text { Examples } \\ \hline \text{Rhombohe} & a=b=c & \alpha=\beta=\gamma & \mathrm{CaCO}_3 \\ \text{dral} & & \neq 90^\circ & \mathrm{HgS} \\ \hline \end{array}\)

Solution:
Correct option is $\mathrm{3}$. Crystal system $=$ Rhombohedral, Axial distance $=a=b=c$, Axial
angles $=\alpha=\beta=\gamma \neq 90^{\circ}$, Examples
$=\mathrm{CaCO}, \mathrm{HgS}$
Rhombohedral crystal system
$a=b=c, \alpha=\beta=\gamma \neq 90^{\circ}$
ex- $\mathrm{NaNO}_3, \mathrm{CaSO}_4$, Calcite $\mathrm{CaCO}_3, \mathrm{HgS}$.

Topic: Chemistry, Solid State, JEE Main
Which of the following is correct about cathode rays?
(i) They are deflected towards the positive plate of the electric field.
(ii) The nature of cathode rays does not depend upon the nature of the material of the cathode.
(iii) The nature of cathode rays depends upon the nature of the gas taken in the discharge tube.
(iv) Cathode rays are made up of electrons.

Options:
A (i) and (ii)
B (ii) and (iv)
C (ii) and (iii)
D (i), (ii), and (iv)

The correct answer is:
(i), (ii), and (iv)

Solution:
Properties of cathode rays are-

Cathode rays consist of negatively charged particles. When cathode rays are subjected to an electrical field, these get deflected towards the positively charged plate i.e. anode. The electrons in the cathode rays would deflect toward the positively charged plates, and away from the negatively charged plates.

Cathode rays do not depend on the nature of gas or the anodes whereas the canal rays do. Since the cathode rays in the discharge tube are the electrons produced due to ionization of gas and that emitted by cathode due to collision of positive ions and are hence independent of the nature of the gas.

Cathode rays are so named because they are emitted by the negative electrode, or cathode, in a vacuum tube. Since the electrons have a negative charge, they are repelled by the cathode and attracted to the anode.

Topic: Chemistry, Structure of Atom, JEE Main
Which of the following is correct about dinoflagellates?

Options:
A The cell wall is made up of a protein-rich layer called a pellicle.
B They have two flagella both arranged longitudinally.
C Rate of reproduction is slow.
D They are mainly responsible for red tides.

The correct answer is:
They are mainly responsible for red tides.

Solution:
The cell wall has stiff cellulose plates on the outer surface. Most of them have two flagella, one lies longitudinally and the other transversely in a furrow between the wall plates. Very often, red dinoflagellates (e.g., Gonyaulax) undergo such rapid multiplication that they make the sea appear red (red tides). Toxins released by such large numbers may even kill other marine animals such as fishes.

Topic: Biology, Biological Classification, NEET
Which of the following is correct about Hardy Weinberg's principle?

Options:
A p2 is the number of pure homozygous dominant individuals in the population, q2 is the number of pure homozygous recessive individuals in the population and 2pq is the number of heterozygous individuals in the population.
B p2 is the number of pure homozygous recessive individuals in the population, q2 is the number of pure homozygous dominant individuals in the population and 2pq is the number of heterozygous individuals in the population.
C p2 is the proportion of pure homozygous dominant individuals in the population, q2 is the proportion of pure homozygous recessive individuals in the population and 2pq is the proportion of heterozygous individuals in the population.
D p2 is the proportion of pure homozygous recessive individuals in the population, q2 is the proportion of pure homozygous dominant individuals in the population and 2pq is the proportion of heterozygous individuals in the population.

The correct answer is:
p2 is the proportion of pure homozygous dominant individuals in the population, q2 is the proportion of pure homozygous recessive individuals in the population and 2pq is the proportion of heterozygous individuals in the population.

Solution:
Hardy was a mathematician and Weinberg was a physician. They devised Hardy- Weinberg principle. According to this principle, the allelic frequencies will remain constant in a population if there is no evolution taking place. In other words, if no evolution takes place the sum of allele frequency will always be equal to one. This is Hardy -Weinberg Equilibrium. Five factors are known to affect Hardy-Weinberg equilibrium. These are gene migration or gene flow, genetic drift, mutation, genetic recombination and natural selection. It is represented by the equation p2 + 2pq + q2 = 1 , where p2 is the proportion of pure homozygous dominant individuals in the population, q2 is the proportion of pure homozygous recessive individuals in the population and 2pq is the proportion of heterozygous individuals in the population.

Topic: Biology, Evolution, NEET
Which of the following is correct about keystone species in an ecosystem?

Options:
A The number is maximum in an ecosystem.
B They aren't required in an ecosystem.
C They have the largest biomass in an ecosystem.
D They are main contributors to ecosystem properties

The correct answer is:
They are main contributors to ecosystem properties

Solution:
The keystone species in an ecosystem are those who are the main contributors to the ecosystem.

Topic: Biology, Ecosystem, NEET
Which of the following is correct about Na+- K+ pump?

Options:
A

3N a + âand â2 K + are transported

B

1N a + âandâ 2 K + are transported

C

3âN a + âandâ 3 K + are transported

D

2N a + âand â3 K + are transported

The correct answer is:

3N a + âand â2 K + are transported

Solution:
During the resting state, the axoplasm inside the axon contains a high concentration of K+ and negatively charged proteins and a low concentration of Na+. In contrast, the fluid outside the axon contains a low concentration of K+, a high concentration of Na+, and thus forms a concentration gradient. These ionic gradients across the resting membrane are maintained by the active transport of ions by the sodium-potassium pump which transports 3Na+ outwards for 2K+ into the cell.

Topic: Biology, Neural Control and Coordination, NEET