datavorous/entrance-exam-dataset huggingface dataset:
Ultraviolet light by wavelength 200 nm is incident on the polished surface of Fe(Iron). The work function of the surface is 4.71 eV. What will be its stopping potential?
h=6.626Ã10-34 J s; 1 eV=1.6Ã10-19 J; C=3Ã108 m s-1

Options:
A 1.5 V

B 2.5 V

C 0.5 V

D None of these

The correct answer is:
1.5 V

Solution:
Stopping potential × energy = KEmax
E= ϕ+kEmax
kEmax=E- ϕ
=hC200 nm-4.71 eV
=6.2 eV-4.71 eV
=1.49 eV ~ 1.5 eV
Stopping potential V=1.5 V

Topic: Physics, Dual Nature of Matter, NEET
Ultraviolet light of wavelength 300 nm and intensity 1.0 W m-2 falls on the surface on photoelectric metal. If one percent of incident photons produce photoelectrons, then the number of photoelectrons emitted from an area of 1.0 cm2 of the surface is nearly

Options:
A 2.13Ã1011Â s-1
B 1.5Ã1012 s-1
C 3.02Ã1012Â s-1
D None of these

The correct answer is:
1.5Ã1012 s-1

Solution:
Energy of each photon = hcλ
= 6.6×10-34×3×108300×10-9
= 6.6×10-19 J
Power of source is given by
p= intensity × area
= 1.0×1.0×10-4 W
= 10-4 W
No. of photons per second
= pe=10-46.6×10-19
Now the number of electrons emitted
= 1100×10-46.6×10-19
=1.5×1012 s-1

Topic: Physics, Dual Nature of Matter, NEET
Ultraviolet radiation of 6.2 eV falls on an aluminium surface (work function 4.2 eV). The kinetic energy of the faster electron emitted is approximately

Options:
A 3.2×10-15 J
B 3.2×10-17 J
C 3.2×10-19 J
D 3.2×10-21 J

The correct answer is:
3.2×10-19 J

Solution:
KE of emitted electron is
EK=h ν-W
= 6.2 eV - 4.2 eV = 2.0 eV
= 2Ã1.6Ã10-19 J
= 3.2Ã10-19J

Topic: Physics, Dual Nature of Matter, NEET
Unbranched stems and pinnate leaves are characteristic features of

Options:
A Pinus
B Sequoia
C Cycas
D Cedrus

The correct answer is:
Cycas

Solution:
In Cycas, the stems are unbranched. The leaves may be simple or compound. Pinnate leaves persist for a few years. The leaves in gymnosperms are well-adapted to withstand extremes of temperature, humidity and wind. In conifers, the needle-like leaves reduce the surface area. Their thick cuticle and sunken stomata also help to reduce water loss.

Topic: Biology, Plant Kingdom, NEET
Uncertainty in position and momentum are equal. Uncertainty in velocity is

Options:
A h2π
B hπ
C 12mhπ
D None of these

The correct answer is:
12mhπ

Solution:
Δp.Δx=h4π
Δp=Δx (Given)
(Δp)2=h4π
(mΔv)2=h4π
Δv=12mhπ

Topic: Chemistry, Structure of Atom, NEET
Under acidic conditions, what products can result from the oxidation of alkenes using acidic potassium permanganate or acidic potassium dichromate?

Options:
A Aldehydes
B Ketones and/or acids
C Alcohols
D Hydrocarbons

The correct answer is:
Ketones and/or acids

Solution:
Under acidic conditions, alkenes can be oxidized using either acidic potassium permanganate or acidic potassium dichromate to produce ketones and/or acids, depending on the nature of the alkene and the experimental conditions.

Topic: Chemistry, Hydrocarbons, NEET
Under favorable conditions, somatic cells store food materials, which become thick-walled structures and are called as

Options:
A Heterocysts
B Akinetes
C Gemmule
D Endospores

The correct answer is:
Akinetes

Solution:
Under favorable conditions, somatic cells store food materials, which become thick-walled called akinetes. They germinate to form new filament and colony.

Topic: Biology, Biological Classification, NEET
Under given suitable conditions, the DPD will be more than OP when

Options:
A OP is equal to TP
B OP is less than TP
C OP is greater than TP
D TP is negative

The correct answer is:
TP is negative

Solution:
DPD=OP âTP . When TP is negative as in a plasmolysed cell than DPD will be more than OP. DPD=OP+TP . In a plasmolysed cell when water from the cytoplasm also moves out than TP becomes negative.

Topic: Biology, Transport in Plants, NEET
Under normal condition which of the given electronic configuration is able to form dipositive ion?

Options:
A Br
B Cl
C Mg
D None of these

The correct answer is:
Mg

Solution:
Mg has only two electrons in the 3s-orbital and hence its I.E. is lowest, i.e. it has the maximum tendency to form di- positive ions.

Topic: Chemistry, Structure of Atom, NEET
Under normal conditions, does hydrogen possess metallic characteristics?

Options:
A Yes
B No
C Can't be predicted
D Rarely

The correct answer is:
No

Solution:
The paragraph mentions that unlike alkali metals, hydrogen does not possess metallic characteristics under normal conditions.

Topic: Chemistry, Hydrogen, NEET
Under normal conditions, how do the densities of liquids compare to gases?

Options:
A Liquids are less dense than gases.
B Liquids are denser than gases.
C Liquids and gases have the same density.
D The densities of liquids and gases vary widely.

The correct answer is:
Liquids are denser than gases.

Solution:
Under normal conditions, liquids are denser than gases.

Topic: Chemistry, States of Matter, NEET
Under normal conditions, which type of elements exist as independent atoms in nature?

Options:
A Noble gases
B Metals
C Nonmetals
D Halogens

The correct answer is:
Noble gases

Solution:
Under normal conditions, only noble gases exist as independent atoms in nature.

Topic: Chemistry, Chemical Bonding and Molecular Structure, NEET
Under normal physiological conditions in human being every 100 ml of oxygenated blood can deliver ___________ ml of O2 to the tissues.

Options:
A 5 ml
B 4 ml
C 10 ml
D 2 ml

The correct answer is:
5 ml

Solution:
Haemoglobin is a red coloured iron containing pigment present in the RBCs. It binds to oxygen in a reversible manner to form oxyhaemoglobin. Each haemoglobin molecule can carry a maximum of
four molecules of oxygen.

The amount of oxygen that binds to the hemoglobin within erythrocytes is primarily related to the oxygen tension which is expressed as the partial pressure of oxygen (pO2). The relationship between the partial pressure of oxygen (pO2) and percentage saturation of the hemoglobin with oxygen (O2) is graphically represented by the oxygen hemoglobin dissociation curve which is sigmoidal under normal conditions.

Every 100 ml of oxygenated blood can deliver around 5 ml of O2 to the tissues under normal physiological
conditions.

Topic: Biology, Breathing and Exchange of Gases, NEET, NEET 2022 (Phase 1)
Under the action of a constant force, a particle is experiencing a constant acceleration. The power is

Options:
A Positive constant
B Negative constant
C Increasing uniformly with time
D Decreasing uniformly with time

The correct answer is:
Increasing uniformly with time

Solution:
Instantaneous power is P=F.v=F at
As force and acceleration are constant.
So, velocity of the particle must be keep on increasing
Hence, power is increasing uniformly with time.
i.e. P∝t .

Topic: Physics, Work Power Energy, NEET
Under the action of a force a 2 kg body moves such that its position x in meters as a function of time t is given by x=t44+3 . Then work done by the force in first two seconds is

Options:
A 6 J
B 10 J
C 7 J
D 64 J

The correct answer is:
64 J

Solution:
x=t44+3
dxdt=4t34+0
v=t3
Using work energy theorem
w=âk=12mv22-12mv02
=122232-03
=64 J

Topic: Physics, Work Power Energy, NEET
Under the assumption that there is no repulsive force between the electrons in an atom but the force between positive and negative charges follows Coulomb's law as usual, what is the calculated ground state energy of a helium atom?

Options:
A –(2×13.6) eV
B –(4×13.6) eV
C –(8×13.6) eV
D –(16×13.6) eV

The correct answer is:
–(4×13.6) eV

Solution:
Correct Option is : (B)
–(4×13.6) eV

Topic: Chemistry, Atomic Physics, NEET
Under the influence of a uniform magnetic field a charged particle is moving in a circle of radius $R$ with constant speed $v$. The time period of the motion:

Options:
A depends on both $R$ and $v$
B is independent of both $R$ and $v$
C depends on $R$ and not on $v$
D depends on $v$ and not on $R$.

The correct answer is:
is independent of both $R$ and $v$

Solution:
$T=\frac{2 \pi m}{q B}$ which is independent of both $R$ and $V$.

Topic: Physics, Magnetic Effects of Current, NEET, NEET 2007
Under the influence of a uniform magnetic field a charged particle is moving in a circle of radius R with constant speed v. The time period of the motion

Options:
A Depends on v and not on R
B Depends on both R and v
C Is independent of both R and v
D Depends on R and not on v

The correct answer is:
Is independent of both R and v

Solution:
When magnetic field is perpendicular to motion of charged particle, then
Centripetal force = magnetic force
ie, mv2R=Bqv
or R=mvBq
Further, time period of the motion
T=2πRv=2πmvBqv
or T=2πmBq
It is independent of both R and v.

Topic: Physics, Magnetic Effects of Current, NEET
Under the influence of a uniform magnetic field, a charged particle moves with constant speed $v$ in a circle of radius $R$. The time period of rotation of the particle

Options:
A depends on $v$ and not on $R$
B depends on $R$ and not on $v$
C is independent of both $v$ and $R$
D depends on both $v$ and $R$

The correct answer is:
is independent of both $v$ and $R$

Solution:
The time period of circular motion of the charged particle is given by
$\begin{aligned}
& \mathrm{T}=\frac{2 \pi \mathrm{r}}{\mathrm{v}}=\frac{2 \pi}{\mathrm{v}} \times \frac{\mathrm{mv}}{\mathrm{Bq}} \\
& \mathrm{T}=\frac{2 \pi \mathrm{m}}{\mathrm{Bq}}
\end{aligned}$
Hence, time period of rotation of the charged particle in uniform magnetic field is independent of both $v$ and $R$.

Topic: Physics, Magnetic Effects of Current, NEET, NEET 2009 (Screening)
Under the isothermal condition, a gas at 300 K expands from 0.1 L to 0.25 L against a constant external pressure of 2 bar. The work done by the gas is

(Given that 1 L bar=100 J)

Options:
A -30 J
B 5Â kJ
C 25Â J
D 30Â J

The correct answer is:
-30 J

Solution:
The work done by a gas,
W=Pexternal×ΔV
=-2×v2-v1
=-2×0.25-0.10
=-0.30 L bar
Given, 1 L bar =100 J.
So, W=-0.3×100=-30 J.

Topic: Chemistry, Thermodynamics (C), NEET, NEET 2019 (All India)
Under the same conditions, how many mL of 1 M KOH and 0.5 M H2SO4 solutions, respectively, when mixed to form at a total volume of 100 mL produces the highest rise in temperature?

Options:
A 67, 33
B 33, 67
C 40, 60
D 50, 50

The correct answer is:
50, 50

Solution:
2KOH(aq)2 mol+H2SO4(aq)1 molâK2SO4+H2O+Heat
Thus, maximum heat is liberated if 2 mol of KOH reacts with 1 mol H2SO4 (or if the ratio of the amounts of KOH to H2SO4 is 2 : 1).
Let x = volume of KOH, then 100 mL â x = volume of H2SO4
Number of mmol KOH =xÃ1 mmol of KOH
Number of mmol of H2SO4=(100-x)Ã0.5 mmol of H2SO4
Maximum heat is liberated if
x m mol of KOH(100-x)Ã0.5 m mol H2SO4=21
So x = 50 mL

Topic: Chemistry, Ionic Equilibrium, NEET
Under the unfavourable condition, the Amoeba withdraws its pseudopodia and secretes a three-layered hard covering or cyst around itself. This phenomenon is termed as

Options:
A

Binary fission

B

Sporulation

C

Budding

D

Encystation

The correct answer is:

Encystation

Solution:
Under the unfavourable condition, the Amoeba withdraws its pseudopodia and secretes a three-layered hard covering or cyst around itself. This phenomenon is termed as encystation. When favourable conditions return, the encysted Amoeba divides by multiple fission and produces many minute Amoeba or pseudopodiospores; the cyst wall bursts out, and the spores are liberated in the surrounding medium to grow up into many amoebae. This phenomenon is known as sporulation.

Topic: Biology, Reproduction in Organisms, NEET
Under what circumstances does hydrometallurgy prove effective in extracting copper, while zinc extraction is not feasible?

Options:
A Zinc forms stable complexes with water, hindering hydrometallurgical processes.
B Zinc has low solubility in water, making it unsuitable for hydrometallurgical extraction.
C Copper exhibits a higher affinity for water, enabling effective hydrometallurgical extraction.
D Zinc reacts chemically with water, impeding the hydrometallurgical process.

The correct answer is:
Zinc has low solubility in water, making it unsuitable for hydrometallurgical extraction.

Solution:
Correct Option is : (B)
Zinc has low solubility in water, making it unsuitable for hydrometallurgical extraction.

Topic: Chemistry, General Principles and Processes of Isolation of Metals, NEET
Under what condition can magnesium reduce alumina?

Options:
A At a temperature below the point of intersection of the Al2O3and MgO curves.
B At a high-pressure point marked "A" in diagram 6.4.
C At a low temperature and low pressure.
D At a high temperature and low pressure.

The correct answer is:
At a temperature below the point of intersection of the Al2O3and MgO curves.

Solution:
Correct Option is : (A)
At a temperature below the point of intersection of the Al2O3and MgO curves.

Topic: Chemistry, General Principles and Processes of Isolation of Metals, NEET
Under what condition do bromides and iodides develop color?

Options:
A When exposed to air
B When heated
C When exposed to light
D When mixed with other halogens

The correct answer is:
When exposed to light

Solution:
Bromides and iodides develop color when exposed to light.

Topic: Chemistry, Haloalkanes and Haloarenes, NEET
Under what condition, the upright pyramid of biomass becomes inverted?

Options:
A Grassland ecosystem
B Terrestrial ecosyslem
C Pond ecosystem
D Tree ecosystem

The correct answer is:
Pond ecosystem

Solution:
Because biomass of each trophic level decreases respectively.

Topic: Biology, Ecosystem, NEET
Under what conditions a bimolecular reaction may be kinetically of first order?

Options:
A When both reactants have same concentration
B When one of the reacting species is in large excess
C When the reaction is at equilibrium
D When the activation energy of reaction is less

The correct answer is:
When one of the reacting species is in large excess

Solution:
If one of the reacting species is in excess, a bimolecular reaction becomes first order reaction. It is generally called as pseudo unimolecular reaction e.g.,
RCOOR'+H2O→RCOOH+R'OH
Here rate =K[RCOOR']1
Here water is in excess so it is neglected.

Topic: Chemistry, Chemical Kinetics, NEET
Under what conditions are carboxylic acids typically heated to form amides from ammonium salts?

Options:
A Low temperature
B Room temperature
C High temperature
D No heating required

The correct answer is:
High temperature

Solution:
Carboxylic acids are typically heated at high temperatures to form amides from the corresponding ammonium salts, as indicated in the paragraph.

Topic: Chemistry, Aldehydes, Ketones and Carboxylic Acids, NEET
Under what conditions are ketones generally oxidized?

Options:
A Mild conditions and low temperatures
B Vigorous conditions, strong oxidizing agents, and elevated temperatures
C Acidic conditions and high pressure
D Alkaline conditions and room temperature

The correct answer is:
Vigorous conditions, strong oxidizing agents, and elevated temperatures

Solution:
Ketones are generally oxidized under vigorous conditions, which involve the use of strong oxidizing agents and elevated temperatures.

Topic: Chemistry, Aldehydes, Ketones and Carboxylic Acids, NEET
Under what conditions are single crystals typically formed?

Options:
A At extremely fast rates of crystallization
B At moderate rates of crystallization
C At extremely slow rates of crystallization
D At any rate of crystallization

The correct answer is:
At extremely slow rates of crystallization

Solution:
Single crystals are typically formed when the process of crystallization occurs at an extremely slow rate.

Topic: Chemistry, Solid State, NEET
Under what conditions can atoms with significantly different energies form molecular orbitals?

Options:
A If they have the same number of electrons
B If they have the same shape
C If they have the same energy
D If they have similar electronegativities

The correct answer is:
If they have similar electronegativities

Solution:
Atoms with significantly different energies can form molecular orbitals if they have similar electronegativities.

Topic: Chemistry, Chemical Bonding and Molecular Structure, NEET
Under what conditions could quartz be converted into glass?

Options:
A By exposing it to extreme heat and then rapidly cooling it.
B By grinding it into fine powder.
C By immersing it in water for an extended period.
D By subjecting it to high pressure.

The correct answer is:
By exposing it to extreme heat and then rapidly cooling it.

Solution:
Correct Option is : (A)
By exposing it to extreme heat and then rapidly cooling it.

Topic: Chemistry, Solid State, NEET
Under what conditions did Gay Lussac observe the behavior of gases in chemical reactions?

Options:
A At different temperatures and pressures
B At the same temperature and different pressures
C At the same temperature and pressure
D At different temperatures and the same pressure

The correct answer is:
At the same temperature and pressure

Solution:
Gay Lussac's observation applies when all gases are at the same temperature and pressure.

Topic: Chemistry, Some Basic Concepts of Chemistry, NEET
Under what conditions do real gases show ideal behavior in terms of pressure?

Options:
A At very high pressure
B At low pressure
C At atmospheric pressure
D As pressure approaches zero

The correct answer is:
As pressure approaches zero

Solution:
Real gases exhibit ideal behavior when pressure approaches zero.

Topic: Chemistry, States of Matter, NEET
Under what conditions does bimolecular dehydration favour the formation of alkenes over ethers?

Options:
A High temperature and hindered alkyl groups
B Low temperature and unhindered alkyl groups
C High temperature and unhindered alkyl groups
D Low temperature and hindered alkyl groups

The correct answer is:
High temperature and hindered alkyl groups

Solution:
High temperature and hindered alkyl groups favour the formation of alkenes over ethers in bimolecular dehydration.

Topic: Chemistry, Alcohols Phenols and Ethers, NEET
Under what conditions does Boyle's law hold true?

Options:
A Constant pressure and volume
B Constant temperature and pressure
C Constant temperature and number of moles
D Constant volume and number of moles

The correct answer is:
Constant temperature and number of moles

Solution:
Boyle's law holds true when there is a constant temperature and a constant number of moles of gas.

Topic: Chemistry, States of Matter, NEET
Under what conditions does fermentation occur?

Options:
A Aerobic conditions
B Anaerobic conditions
C Aerobic respiration
D Krebs' cycle

The correct answer is:
Anaerobic conditions

Solution:
Fermentation takes place under anaerobic conditions in many prokaryotes and unicellular eukaryotes.

Topic: Biology, Respiration in Plants, NEET
Under what conditions does hydrogen peroxide decompose?

Options:
A Only in the presence of metal surfaces
B Only in the presence of traces of alkali
C Only on exposure to light
D All of the above

The correct answer is:
All of the above

Solution:
Hydrogen peroxide can decompose in the presence of metal surfaces, traces of alkali, and on exposure to light.

Topic: Chemistry, Hydrogen, NEET
Under what conditions does SiO exist?

Options:
A At low temperature
B At room temperature
C At high temperature
D In the presence of water

The correct answer is:
At high temperature

Solution:
SiO only exists at high temperature.

Topic: Chemistry, p Block Elements (Group 13 & 14), NEET
Under what conditions does the cleavage of the C-O bond in ethers typically occur?

Options:
A Mild conditions
B Acidic conditions
C Drastic conditions with excess hydrogen halides
D Alkaline conditions

The correct answer is:
Drastic conditions with excess hydrogen halides

Solution:
The passage mentions that the cleavage of the C-O bond in ethers takes place under drastic conditions with excess hydrogen halides.

Topic: Chemistry, Alcohols Phenols and Ethers, NEET
Under what conditions does the equilibrium quotient change when an inert gas is added?

Options:
A The equilibrium quotient always changes when an inert gas is added.
B The equilibrium quotient changes only if the added gas is a reactant or product involved in the reaction.
C The equilibrium quotient changes only if the added gas is at a high pressure.
D The equilibrium quotient changes only if the added gas is at a low temperature.

The correct answer is:
The equilibrium quotient changes only if the added gas is a reactant or product involved in the reaction.

Solution:
The equilibrium quotient changes only if the added gas is a reactant or product involved in the reaction, not when an inert gas is added.

Topic: Chemistry, Chemical Equilibrium, NEET
Under what conditions glucose is converted to gluconic and saccharic acid?

Options:
A Glucose is converted to gluconic and saccharic acid under acidic conditions.
B Glucose is converted to gluconic and saccharic acid under reducing conditions.
C Glucose is converted to gluconic acid by HNO3and to saccharic acid by Bromine water
D Glucose is converted to gluconic acid by bromine water and to saccharic acid by conc.HNO3.

The correct answer is:
Glucose is converted to gluconic acid by bromine water and to saccharic acid by conc.HNO3.

Solution:
Correct Option is : (D)
Glucose is converted to gluconic acid by bromine water and to saccharic acid by conc.HNO3.

Topic: Chemistry, Biomolecules, NEET
Under what conditions is a chemical reaction considered feasible?

Options:
A When the temperature is constant
B When the pressure is constant
C When ΔG is greater than zero
D When ΔG is less than zero at constant temperature and pressure

The correct answer is:
When ΔG is less than zero at constant temperature and pressure

Solution:
A reaction with ΔG < 0, at constant temperature and pressure, is considered feasible.

Topic: Chemistry, Chemical Kinetics, NEET
Under what conditions is atomic hydrogen produced?

Options:
A At low temperatures
B In the presence of water vapor
C At high temperatures, such as in an electric arc or under ultraviolet radiations
D In the absence of oxygen

The correct answer is:
At high temperatures, such as in an electric arc or under ultraviolet radiations

Solution:
Atomic hydrogen is produced at high temperatures, such as in an electric arc or under ultraviolet radiations.

Topic: Chemistry, Hydrogen, NEET
Under what conditions is the subscript 'system' usually dropped in the Gibbs energy equation?

Options:
A In closed systems
B In open systems
C At constant temperature
D At constant pressure

The correct answer is:
At constant temperature

Solution:
The subscript 'system' is usually dropped in the Gibbs energy equation when the process is considered at constant temperature.

Topic: Chemistry, Thermodynamics (C), NEET
Under what conditions of temperature and pressure the formation of atomic hydrogen from molecular hydrogen will be favoured most?

Options:
A High temperature and high pressure
B Low temperature and low pressure
C High temperature and low pressure
D Low temperature and high pressure

The correct answer is:
High temperature and low pressure

Solution:
H2(g)→2H(g)
As temperature increases and pressure decreases, formation of atomic H increases. As it is endothermic process and volume is increasing so high temperature and low pressure are favourable for forward reaction.

Topic: Chemistry, s Block Elements, NEET
Under what conditions will a pure sample of an ideal gas not only exhibit a pressure of 1 atm but also a concentration of 1 mol litre -1 ?

Options:
A At STP
B When V = 22.4 litre
C When T = 12 K
D Impossible under any condition

The correct answer is:
When T = 12 K

Solution:
Use PV = nRT
P = 1
nV=1
So T=1R=12 K
So at 12 K temperature, the value of pressure and molar concentration is unity.

Topic: Chemistry, States of Matter, NEET
Under what conditions will a pure sample of an ideal gas not only exhibit a pressure of 1 atm, but also a concentration of 1 mole litre-1 ?(R = 0.082 litre atm mol-1deg-1 )

Options:
A At STP
B When V = 22.4
C When T = 12 K
D Impossible under any condition

The correct answer is:
When T = 12 K

Solution:
The gas has a concentration of 1 mol/L.
This means that V = 1
Number of mol of gas (n) = 1​ mol
P = 1 atm
R = 0.082 L atm mol  K −1
T = ?
So PV=nRT
So T=PVnR
=  1 atm × 1 L 1 mol × 0.082 L atm  mol −1   K −1
=  1 0.082  = 12 K

Topic: Chemistry, States of Matter, NEET