datavorous/entrance-exam-dataset huggingface dataset:
Why do para-isomers have higher melting points compared to ortho- and meta-isomers?

Options:
A They have greater polarity.
B They have lower molecular mass.
C They are less symmetric.
D They fit better in a crystal lattice due to symmetry.

The correct answer is:
They fit better in a crystal lattice due to symmetry.

Solution:
The higher melting points of para-isomers are due to their symmetry, which allows them to fit better in a crystal lattice.

Topic: Chemistry, Haloalkanes and Haloarenes, NEET
Why do passengers get thrown forward from their seats when a speeding bus stops suddenly?

Options:
A Due to increased gravitational force
B Because of inertia
C As a result of air resistance
D Because of magnetic attraction

The correct answer is:
Because of inertia

Solution:
Correct Option is : (B)
Because of inertia

Topic: Chemistry, Laws of Motion, NEET
Why do pentahalides exhibit more covalent character than trihalides?

Options:
A Pentahalides have a higher atomic number
B Pentahalides involve +3 oxidation state
C Pentahalides involve +5 oxidation state
D It varies depending on the element

The correct answer is:
Pentahalides involve +5 oxidation state

Solution:
The covalent character of pentahalides is attributed to the +5 oxidation state, which has more polarizing power compared to +3 oxidation state in trihalides.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
Why do people prefer steel utensils with a copper bottom for uniform heating of food?

Options:
A Steel and copper together provide uniform heating due to their balanced conductivity.
B The quick heating of the copper bottom ensures even distribution of heat in the steel utensil.
C Copper's higher conductivity results in rapid heating at the junction, leading to uniform heating of the food.
D The use of steel with copper allows for better insulation, ensuring uniform heating of the food.

The correct answer is:
Copper's higher conductivity results in rapid heating at the junction, leading to uniform heating of the food.

Solution:
Correct Option is : (C)
Copper's higher conductivity results in rapid heating at the junction, leading to uniform heating of the food.

Topic: Chemistry, Thermal Properties of Matter, NEET
Why do phenols generally have higher boiling points compared to ethers of similar molecular mass?

Options:
A Phenols have aromatic rings
B Phenols form hydrogen bonds with water
C Ethers have stronger van der Waals forces
D Ethers lack hydrogen atoms

The correct answer is:
Phenols form hydrogen bonds with water

Solution:
The ability of phenols to form hydrogen bonds with water contributes to their higher boiling points.

Topic: Chemistry, Alcohols Phenols and Ethers, NEET
Why do phenols not react further to give halides?

Options:
A Phenols are unreactive.
B Phenols lack a leaving group.
C Phenols cannot undergo nucleophilic substitution reactions.
D Phenols are highly stable.

The correct answer is:
Phenols cannot undergo nucleophilic substitution reactions.

Solution:
Phenols do not react further to give halides because the sp2 hybridised carbon of phenol cannot undergo nucleophilic substitution reactions required for the conversion to halides.

Topic: Chemistry, Alcohols Phenols and Ethers, NEET
Why do phosphorus and arsenic have a greater covalency than nitrogen?

Options:
A Smaller atomic size
B Presence of d orbitals
C Higher ionization enthalpy
D Higher electronegativity

The correct answer is:
Presence of d orbitals

Solution:
Phosphorus and arsenic have a greater covalency than nitrogen because they have vacant d orbitals in their outermost shell, which allows them to form more bonds.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
Why do physisorption and chemisorption behave differently with the rise in temperature?

Options:
A Physisorption is exothermic, while chemisorption is endothermic.
B Physisorption is entropy-driven, while chemisorption is enthalpy-driven.
C Physisorption is favored at higher temperatures, while chemisorption is favored at lower temperatures.
D Physisorption is reversible, while chemisorption is irreversible.

The correct answer is:
Physisorption is favored at higher temperatures, while chemisorption is favored at lower temperatures.

Solution:
Correct Option is : (C)
Physisorption is favored at higher temperatures, while chemisorption is favored at lower temperatures.

Topic: Chemistry, Surface Chemistry, NEET
Why do plants not have great demands for gas exchange?

Options:
A Because each plant part takes care of its own gas-exchange needs
B Because there is transport of gases from one plant part to another
C Because plants respire at high rates
D Because each leaf is well adapted for gas exchange during photosynthesis

The correct answer is:
Because each plant part takes care of its own gas-exchange needs

Solution:
Each plant part takes care of its own gas-exchange needs, so plants do not have great demands for gas exchange.

Topic: Biology, Respiration in Plants, NEET
Why do real gases deviate from the ideal gas law?

Options:
A Real gases have a different molecular composition.
B Real gases are not subject to high pressures.
C Molecular interactions between gas molecules come into play at high pressures.
D Real gases have a different temperature range.

The correct answer is:
Molecular interactions between gas molecules come into play at high pressures.

Solution:
Real gases deviate from the ideal gas law because at high pressures, molecules of gases are very close to each other, leading to molecular interactions that affect the pressure exerted by the gas.

Topic: Chemistry, States of Matter, NEET
Why do receptors in the body show selectivity for different chemical messengers?

Options:
A Because they have the same shape and structure
B Because they have different binding sites
C Because they have the same amino acid composition
D Because they interact with only one type of chemical messenger

The correct answer is:
Because they have different binding sites

Solution:
Receptors show selectivity for different chemical messengers because their binding sites have different shapes, structures, and amino acid compositions.

Topic: Chemistry, Chemistry in Everyday Life, NEET
Why do soaps not work effectively in hard water?

Options:
A Because hard water contains calcium and magnesium ions
B Because hard water is too cold for soap to dissolve
C Because hard water contains excessive sodium ions
D Because hard water contains chlorine ions

The correct answer is:
Because hard water contains calcium and magnesium ions

Solution:
Soaps do not work effectively in hard water because hard water contains calcium and magnesium ions, which form insoluble calcium and magnesium soaps when sodium or potassium soaps are dissolved in it.

Topic: Chemistry, Chemistry in Everyday Life, NEET
Why do soaps not work in hard water?

Options:
A Soaps react with minerals in hard water and become ineffective.
B Soaps form scum in hard water, reducing their cleaning ability.
C Soaps do not lather well in the presence of certain ions in hard water.
D Soaps become too slippery to use in hard water.

The correct answer is:
Soaps do not lather well in the presence of certain ions in hard water.

Solution:
Correct Option is : (C)
Soaps do not lather well in the presence of certain ions in hard water.

Topic: Chemistry, Chemistry in Everyday Life, NEET
Why do solids have a definite volume?

Options:
A Because their particles are closely packed.
B Because their particles have high kinetic energy.
C Because their particles are constantly moving.
D Because their particles have low density.

The correct answer is:
Because their particles are closely packed.

Solution:
Correct Option is : (A)
Because their particles are closely packed.

Topic: Chemistry, Solid State, NEET
Why do some elements have exceptions to the general electronic configuration due to the energy difference between (n-1)d and ns orbitals?

Options:
A Because (n-1)d orbitals can hold more electrons
B Because the energy gap between (n-1)d and ns orbitals is small
C Because (n-1)d orbitals have a higher energy level
D Because the ns orbitals are completely filled

The correct answer is:
Because the energy gap between (n-1)d and ns orbitals is small

Solution:
The (n–1) stands for the inner d orbitals which may have one to ten electrons and the outermost ns orbital may have one or two electrons. However, this generalisation has several exceptions because of very little energy difference between (n-1)d and ns orbitals

Topic: Chemistry, d and f Block Elements, NEET
Why do some metals like Cr and Al not dissolve in concentrated nitric acid?

Options:
A Because they form passive films of oxide on the surface
B Because they react violently with the acid
C Because they are noble metals
D Because they are insoluble in all acids

The correct answer is:
Because they form passive films of oxide on the surface

Solution:
The paragraph explains that some metals like Cr and Al do not dissolve in concentrated nitric acid because they form passive films of oxide on the surface.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
Why do some substances behave as insulators?

Options:
A Because they have a large number of valence electrons.
B Because the gap between the valence band and the conduction band is small.
C Because the gap between the valence band and the conduction band is large.
D Because they are in the liquid state.

The correct answer is:
Because the gap between the valence band and the conduction band is large.

Solution:
Substances behave as insulators when the gap between the valence band and the conduction band (the band gap) is large, preventing electrons from jumping to the conduction band and resulting in very small conductivity.

Topic: Chemistry, Solid State, NEET
Why do the alkaline earth metals have higher melting and boiling points than the corresponding alkali metals?

Options:
A Due to their larger sizes
B Due to their smaller sizes
C Due to the presence of more protons
D Due to their lower ionization energies

The correct answer is:
Due to their larger sizes

Solution:
The alkaline earth metals have larger atomic sizes compared to the alkali metals in Group 1, which leads to stronger metallic bonding and higher melting and boiling points.

Topic: Chemistry, s Block Elements, NEET
Why do the antihistamines not affect the secretion of acid in the stomach?

Options:
A They are ineffective drugs.
B They do not compete with histamine.
C They work on different receptors.
D They stimulate acid secretion.

The correct answer is:
They work on different receptors.

Solution:
Antiallergic and antacid drugs do not affect the secretion of acid in the stomach because they work on different receptors.

Topic: Chemistry, Chemistry in Everyday Life, NEET
Why do the boiling points of alcohol decrease with an increase in branching in the carbon chain?

Options:
A Increase in hydrogen bonding
B Decrease in van der Waals forces
C Increase in surface area
D Decrease in dipole-dipole interactions

The correct answer is:
Decrease in van der Waals forces

Solution:
Branching in the carbon chain decreases surface area, reducing van der Waals forces and thus lowering boiling points.

Topic: Chemistry, Alcohols Phenols and Ethers, NEET
Why do the boiling points of chlorides, bromides, and iodides of organic compounds tend to be higher than those of hydrocarbons with comparable molecular mass?

Options:
A Due to lower polarity
B Due to weaker intermolecular forces
C Due to the presence of hydrogen atoms
D Due to greater polarity and stronger intermolecular forces

The correct answer is:
Due to greater polarity and stronger intermolecular forces

Solution:
The boiling points of chlorides, bromides, and iodides are higher than those of hydrocarbons with comparable molecular mass because of their greater polarity and stronger intermolecular forces.

Topic: Chemistry, Haloalkanes and Haloarenes, NEET
Why do the elements in pentahalides have more polarizing power?

Options:
A They have smaller atomic sizes
B They have lower electronegativity
C They have a higher ionization energy
D They have greater nuclear charge

The correct answer is:
They have greater nuclear charge

Solution:
Elements in pentahalides have more polarizing power because of their higher +5 oxidation state and greater nuclear charge.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
Why do the Eo values for the M2+/M redox couples in the first row transition metals show irregularities?

Options:
A Due to differences in atomic size
B Due to irregular variation of ionization enthalpies and sublimation enthalpies
C Due to the presence of d electrons
D Due to the number of protons in the nucleus

The correct answer is:
Due to irregular variation of ionization enthalpies and sublimation enthalpies

Solution:
The irregularities in the Eo values for the M2+/M redox couples can be explained by the irregular variation of ionization enthalpies and sublimation enthalpies.

Topic: Chemistry, d and f Block Elements, NEET
Why do the following reactions proceed differently?
1. \(\mathrm{Pb}_3 \mathrm{O}_4+8 \mathrm{HCl} \rightarrow 3 \mathrm{PbCl}_2+\mathrm{Cl}_2+4 \mathrm{H}_2 \mathrm{O}\)
2. \(\mathrm{Pb}_3 \mathrm{O}_4+4 \mathrm{HNO}_3 \rightarrow 2 \mathrm{~Pb}\left(\mathrm{NO}_3\right)_2+\mathrm{PbO}_2+2 \mathrm{H}_2 \mathrm{O}\)

Options:
A Different reactants are involved.
B Different oxidizing agents are used.
C Different reducing agents are used.
D Different reaction conditions are applied.

The correct answer is:
Different oxidizing agents are used.

Solution:
Correct Option is : (B)
Different oxidizing agents are used.

Topic: Chemistry, Redox Reactions, NEET
Why do the second and third d series exhibit similar radii and very similar physical and chemical properties?

Options:
A Due to the intervention of the 4f orbitals.
B Due to the imperfect shielding of one electron by another in the same set of orbitals.
C Due to the net electrostatic attraction between the nuclear charge and the outermost electron.
D Due to the decrease in metallic radius.

The correct answer is:
Due to the intervention of the 4f orbitals.

Solution:
The second and third d series exhibit similar radii and properties because of the intervention of the 4f orbitals.

Topic: Chemistry, d and f Block Elements, NEET
Why do the sp hybrid orbitals provide more effective overlapping?

Options:
A Because they have a random orientation.
B Because they have the same lobe orientation.
C Because they have opposite lobe orientations.
D Cannot be determined.

The correct answer is:
Because they have opposite lobe orientations.

Solution:
The sp hybrid orbitals provide more effective overlapping because they have projecting positive lobes and very small negative lobes with opposite orientations.

Topic: Chemistry, Chemical Bonding and Molecular Structure, NEET
Why do the three quantum numbers (n, l, ml) alone not explain the line spectra observed in multi-electron atoms?

Options:
A Because the quantum numbers do not consider the electron's energy levels.
B Because the quantum numbers do not account for the electron's spin.
C Because the quantum numbers do not consider the electron's size.
D Because the quantum numbers do not account for the electron's orientation.

The correct answer is:
Because the quantum numbers do not account for the electron's spin.

Solution:
The three quantum numbers (n, l, ml) can define an atomic orbital energy, shape, and orientation, but they do not account for the electron's spin, which is necessary to explain the line spectra in multi-electron atoms.

Topic: Chemistry, Structure of Atom, NEET
Why do the transition elements exhibit higher enthalpies of atomisation?

Options:
A Because Transition elements have more protons in their nuclei.
B Because Transition elements have a larger number of valence electrons.
C Because of the large number of unpaired electrons in their atoms they have stronger interatomic interaction and hence stronger bonding between atoms resulting in higher enthalpies of atomisation.
D Because Transition elements have a smaller atomic radius compared to other elements.

The correct answer is:
Because of the large number of unpaired electrons in their atoms they have stronger interatomic interaction and hence stronger bonding between atoms resulting in higher enthalpies of atomisation.

Solution:
Correct Option is : (C)
Because of the large number of unpaired electrons in their atoms they have stronger interatomic interaction and hence stronger bonding between atoms resulting in higher enthalpies of atomisation.

Topic: Chemistry, d and f Block Elements, NEET
Why do vehicles carrying inflammable materials usually have metallic ropes touching the ground during motion?

Options:
A To reduce static electricity buildup
B To improve vehicle stability
C To increase fuel efficiency
D To enhance braking performance

The correct answer is:
To reduce static electricity buildup

Solution:
Correct Option is : (A)
To reduce static electricity buildup

Topic: Chemistry, Capacitance, NEET
Why do we add alum to purify water?

Options:
A Alum kills harmful bacteria in water.
B Alum neutralizes acidity in water.
C Alum helps in the coagulation of impurities, making them settle down.
D Alum enhances the taste of water.

The correct answer is:
Alum helps in the coagulation of impurities, making them settle down.

Solution:
Correct Option is : (C)
Alum helps in the coagulation of impurities, making them settle down.

Topic: Chemistry, Surface Chemistry, NEET
Why do we get isopropyl benzene on treating benzene with 1-chloropropane instead of n-propyl benzene?

Options:
A The reaction is selective for the formation of isopropyl benzene.
B Isopropyl chloride is more reactive than n-propyl chloride.
C Steric hindrance favors the formation of isopropyl benzene.
D Thermodynamic stability leads to the formation of isopropyl benzene.

The correct answer is:
Steric hindrance favors the formation of isopropyl benzene.

Solution:
The formation of isopropyl benzene is favored due to steric hindrance. The isopropyl group is smaller and less bulky than the n-propyl group, allowing for easier electrophilic substitution on the benzene ring.

Topic: Chemistry, Hydrocarbons, NEET
Why do we keep food in the refrigerator?

Options:
A To prevent food from going bad due to bacterial or fungal infections
B To keep food fresh for a longer period of time
C To make food cold before eating
D To prevent food from being contaminated

The correct answer is:
To prevent food from going bad due to bacterial or fungal infections

Solution:
We keep food in the refrigerator to prevent food from going bad due to bacterial or fungal infections. This is because fungi prefer to grow in warm and humid places, and the refrigerator helps to slow down the growth of these organisms

Topic: Biology, Biological Classification, NEET
Why do we need to classify drugs in different ways?

Options:
A To make them easier to manufacture
B To regulate their prices
C To understand their properties and effects
D To control their distribution

The correct answer is:
To understand their properties and effects

Solution:
Correct Option is : (C)
To understand their properties and effects

Topic: Chemistry, Chemistry in Everyday Life, NEET
Why do we observe an unexpected trend in the order of basicity in aqueous phase in methylamine and ethylamine derivatives?

Options:
A Steric Inhibition of Protonation effect
B Solvation effect
C Steric hindrance
D Both B and C

The correct answer is:
Both B and C

Solution:
Correct Option is : 4
Both B and C

Topic: Chemistry, Amines, NEET
Why do we require artificial sweetening agents?

Options:
A To enhance the flavor of food and drinks.
B To provide essential nutrients.
C To replace natural sugars for diabetic individuals.
D To increase the shelf-life of products.

The correct answer is:
To replace natural sugars for diabetic individuals.

Solution:
Correct Option is : (C)
To replace natural sugars for diabetic individuals.

Topic: Chemistry, Chemistry in Everyday Life, NEET
Why do white fumes appear around the bottle of anhydrous aluminum chloride?

Options:
A Due to the formation of water vapor
B Due to the sublimation of aluminum chloride
C Due to the release of hydrogen gas
D Due to the hydrolysis of aluminum chloride

The correct answer is:
Due to the hydrolysis of aluminum chloride

Solution:
The white fumes appear because anhydrous aluminum chloride is partially hydrolyzed with atmospheric moisture, liberating HCl gas, which appears white in color.

Topic: Chemistry, p Block Elements (Group 13 & 14), NEET
Why does 1g of activated charcoal adsorb more sulphur dioxide than methane?

Options:
A Methane has a higher critical temperature.
B Sulphur dioxide has a higher critical temperature.
C Methane has a lower critical temperature.
D Sulphur dioxide has a lower critical temperature.

The correct answer is:
Sulphur dioxide has a higher critical temperature.

Solution:
The paragraph mentions that activated charcoal adsorbs more sulphur dioxide than methane, and it explains that easily liquefiable gases with higher critical temperatures are more readily adsorbed.

Topic: Chemistry, Surface Chemistry, NEET
Why does 2,2-dimethylpropane have a lower boiling point than pentane?

Options:
A It has a lower molecular mass.
B It has stronger hydrogen bonding.
C It has a linear shape.
D It has a spherical shape with fewer points of contact.

The correct answer is:
It has a spherical shape with fewer points of contact.

Solution:
2,2-dimethylpropane has a lower boiling point than pentane because its spherical shape reduces the surface area of contact, leading to weaker intermolecular forces.

Topic: Chemistry, Hydrocarbons, NEET
Why does a balanced chemical equation not provide a true picture of how a reaction takes place?

Options:
A It lacks information about the products of the reaction.
B It does not include the stoichiometric coefficients.
C Most reactions involve multiple steps.
D It cannot be accurately balanced.

The correct answer is:
Most reactions involve multiple steps.

Solution:
A balanced chemical equation does not provide a true picture of a reaction because most reactions involve multiple steps, not just a single step.

Topic: Chemistry, Chemical Kinetics, NEET
Why does a brass tumbler feel much colder than a wooden tray on a chilly day?

Options:
A Because brass conducts heat more effectively than wood.
B Due to the difference in their thermal properties.
C Because brass has a lower specific heat capacity compared to wood.
D Because wooden trays are insulated against temperature changes.

The correct answer is:
Because brass conducts heat more effectively than wood.

Solution:
Correct Option is : (A)
Because brass conducts heat more effectively than wood.

Topic: Chemistry, Thermal Properties of Matter, NEET
Why does a child feel more pain when falling on a hard cement floor compared to a soft muddy ground in the garden?

Options:
A The cement floor is more slippery, causing greater impact.
B The child's shoes provide less cushioning on the cement floor.
C The mud floor reduces the force of impact due to yielding and a longer time to come to rest.
D The child's body reacts differently to various types of ground.

The correct answer is:
The mud floor reduces the force of impact due to yielding and a longer time to come to rest.

Solution:
Correct Option is : (C)
The mud floor reduces the force of impact due to yielding and a longer time to come to rest.

Topic: Chemistry, Laws of Motion, NEET
Why does a cricketer move his hands backward while holding a catch?

Options:
A To align with the trajectory of the ball
B To increase the time of impact with the ball
C To intimidate the batsman
D To improve their posture

The correct answer is:
To increase the time of impact with the ball

Solution:
Correct Option is : (B)
To increase the time of impact with the ball

Topic: Chemistry, Laws of Motion, NEET