datavorous/entrance-exam-dataset huggingface dataset:
What is the primary reason for nitrogen not forming pentahalides?

Options:
A Lack of reactivity with halogens
B Non-availability of d orbitals
C Low atomic size
D Presence of a stable isotope

The correct answer is:
Non-availability of d orbitals

Solution:
Nitrogen does not form pentahalides because it lacks d orbitals in its valence shell.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
What is the primary reason for sodium having lower reducing power compared to lithium?

Options:
A Higher ionization enthalpy
B Smaller ion size
C Lower hydration enthalpy
D Greater electronegativity

The correct answer is:
Higher ionization enthalpy

Solution:
Sodium (Na) has lower reducing power compared to lithium (Li) primarily due to its higher ionization enthalpy. Higher ionization enthalpy means it is less likely to lose an electron and act as a reducing agent.

Topic: Chemistry, s Block Elements, NEET
What is the primary reason for the acidic character of alcohols?

Options:
A The presence of a hydroxyl group (-OH)
B The presence of a carbonyl group (C=O)
C The presence of a halogen atom (e.g., Cl)
D The presence of a nitro group (-NO2)

The correct answer is:
The presence of a hydroxyl group (-OH)

Solution:
The acidic character of alcohols is primarily due to the polar O-H bond in the hydroxyl group (-OH).

Topic: Chemistry, Alcohols Phenols and Ethers, NEET
What is the primary reason for the alkaline earth metals being strongly electropositive in nature?

Options:
A High ionization energies
B Large atomic sizes
C Low ionization energies
D High electronegativity

The correct answer is:
Low ionization energies

Solution:
The alkaline earth metals are strongly electropositive in nature due to their low ionization energies, which means they readily lose electrons to form positive ions.

Topic: Chemistry, s Block Elements, NEET
What is the primary reason for the anisotropic nature of crystalline solids?

Options:
A The presence of long-range order in their arrangement
B The absence of long-range order in their arrangement
C Their transparency
D Their high electrical conductivity

The correct answer is:
The presence of long-range order in their arrangement

Solution:
The anisotropic nature of crystalline solids is primarily due to the presence of long-range order in their arrangement, as mentioned in the paragraph.

Topic: Chemistry, Solid State, NEET
What is the primary reason for the anomalous behavior of fluorine among the halogens?

Options:
A Its high ionization energy
B Its low electronegativity
C Its availability of d orbitals in the valence shell
D Its small size, high electronegativity, and low F-F bond dissociation enthalpy

The correct answer is:
Its small size, high electronegativity, and low F-F bond dissociation enthalpy

Solution:
The anomalous behavior of fluorine is primarily due to its small size, high electronegativity, and low F-F bond dissociation enthalpy.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
What is the primary reason for the anomalous behavior of oxygen and other second-period p-block elements?

Options:
A Low electronegativity
B Small size and high electronegativity
C High atomic mass
D Metallic bonding

The correct answer is:
Small size and high electronegativity

Solution:
The paragraph attributes the anomalous behavior of oxygen and other second-period p-block elements to their small size and high electronegativity.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
What is the primary reason for the chemistry of the lanthanoids being an excellent opportunity for studying the effects of small changes in size and nuclear charge?

Options:
A Their high reactivity
B Their wide range of oxidation states
C Their similarity to transition elements
D Their close resemblance to each other

The correct answer is:
Their close resemblance to each other

Solution:
The lanthanoids resemble one another closely, making them suitable for studying the effects of small changes in size and nuclear charge.

Topic: Chemistry, d and f Block Elements, NEET
What is the primary reason for the color differences among the halogens?

Options:
A Atomic radius
B Electron configuration
C Atomic mass
D Ionization energy

The correct answer is:
Electron configuration

Solution:
The color differences among the halogens are primarily due to their electron configuration, which results in the excitation of their outer electrons to higher energy levels, leading to different colors.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
What is the primary reason for the color differences among the halogens?

Options:
A Atomic radius
B Electron configuration
C Atomic mass
D Ionization energy

The correct answer is:
Electron configuration

Solution:
The color differences among the halogens are primarily due to their electron configuration, which results in the excitation of outer electrons to higher energy levels, leading to different colors.**

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
What is the primary reason for the conducting nature of alkali metal solutions in liquid ammonia?

Options:
A Presence of metal cations
B Presence of ammoniated electrons
C Presence of ammonia molecules
D Presence of hydrogen ions

The correct answer is:
Presence of ammoniated electrons

Solution:
The conducting nature of alkali metal solutions in liquid ammonia is primarily due to the presence of ammoniated electrons.

Topic: Chemistry, s Block Elements, NEET
What is the primary reason for the decrease in temperature with an increase in altitude?

Options:
A Increase in molecular potential energy
B Decrease in atmospheric pressure
C Expansion of gas molecules at higher altitudes
D Reduction in kinetic energy of the molecules

The correct answer is:
Reduction in kinetic energy of the molecules

Solution:
Correct Option is : (D)
Reduction in kinetic energy of the molecules

Topic: Chemistry, Kinetic Theory of Gases, NEET
What is the primary reason for the differences in properties between crystalline and amorphous solids?

Options:
A Their color
B Their mass
C The arrangement of constituent particles
D Their density

The correct answer is:
The arrangement of constituent particles

Solution:
The primary reason for the differences in properties between crystalline and amorphous solids is the arrangement of their constituent particles, as mentioned in the paragraph.

Topic: Chemistry, Solid State, NEET
What is the primary reason for the distinctiveness of transition elements?

Options:
A Their high atomic numbers
B The presence of partly filled d or f orbitals
C Their position in the s-block
D Their strong metallic bonding

The correct answer is:
The presence of partly filled d or f orbitals

Solution:
The presence of partly filled d or f orbitals is the primary reason for the distinctiveness of transition elements.

Topic: Chemistry, d and f Block Elements, NEET
What is the primary reason for the explosive reaction of potassium with water?

Options:
A High electronegativity of potassium
B Large size of potassium atoms
C High hydration energy of potassium
D Low ionization energy of potassium

The correct answer is:
Low ionization energy of potassium

Solution:
The explosive reaction of potassium with water is primarily due to its low ionization energy, which allows for a rapid release of energy and ignition of hydrogen gas.

Topic: Chemistry, s Block Elements, NEET
What is the primary reason for the foul smell produced when anaerobic bacteria break down organic waste in water?

Options:
A High oxygen levels
B High dissolved oxygen
C Presence of sulfur compounds
D Presence of oxygen-dependent bacteria

The correct answer is:
Presence of sulfur compounds

Solution:
The foul smell produced by anaerobic bacteria is often due to the presence of sulfur compounds in the breakdown process.

Topic: Chemistry, Environmental Chemistry, NEET
What is the primary reason for the "green fuel" obtained from plastic waste being called "green"?

Options:
A It has a green color.
B It is derived from plants.
C It is environmentally friendly.
D It is made from recycled materials.

The correct answer is:
It is environmentally friendly.

Solution:
The term "green" in "green fuel" typically refers to the environmental friendliness of the fuel, indicating that it is produced or used in a way that has a reduced impact on the environment.

Topic: Chemistry, Environmental Chemistry, NEET
What is the primary reason for the high electrical and thermal conductivities of alkaline earth metals?

Options:
A High ionization energies
B High melting points
C Presence of free electrons in the metal lattice
D Small atomic sizes

The correct answer is:
Presence of free electrons in the metal lattice

Solution:
The high electrical and thermal conductivities of metals are primarily due to the presence of free electrons in the metal lattice that can move freely and carry electrical and thermal energy.

Topic: Chemistry, s Block Elements, NEET
What is the primary reason for the high enthalpy of chemisorption?

Options:
A Weak van der Waals' forces
B High energy of activation
C Formation of strong covalent bonds
D Endothermic nature of the process

The correct answer is:
Formation of strong covalent bonds

Solution:
The paragraph mentions that the enthalpy of chemisorption is high (80-240 kJ mol-1) because it involves chemical bond formation.

Topic: Chemistry, Surface Chemistry, NEET
What is the primary reason for the high ionisation enthalpy of halogens?

Options:
A Maximum number of quantum shells
B Strong attraction in the 2p orbitals
C Small atomic size
D High electron gain enthalpy

The correct answer is:
Small atomic size

Solution:
The high ionisation enthalpy of halogens is primarily due to their small atomic size, which results in strong attraction between the nucleus and the outermost electrons.**

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
What is the primary reason for the higher electronegativity of group 14 elements?

Options:
A Their larger atomic size
B Their smaller atomic size
C Their higher atomic number
D Their greater number of valence electrons

The correct answer is:
Their smaller atomic size

Solution:
The higher electronegativity of group 14 elements is due to their small size.

Topic: Chemistry, p Block Elements (Group 13 & 14), NEET
What is the primary reason for the increase in boiling points of alcohols and phenols with an increase in the number of carbon atoms?

Options:
A Decrease in van der Waals forces
B Increase in van der Waals forces
C Decrease in hydrogen bonding
D Increase in branching

The correct answer is:
Increase in van der Waals forces

Solution:
Boiling points increase with an increase in the number of carbon atoms due to increased van der Waals forces.

Topic: Chemistry, Alcohols Phenols and Ethers, NEET
What is the primary reason for the low melting and boiling points of alkali metals?

Options:
A Strong metallic bonding
B High number of valence electrons
C Weak metallic bonding due to a single valence electron
D Presence of multiple valence electrons

The correct answer is:
Weak metallic bonding due to a single valence electron

Solution:
The low melting and boiling points of alkali metals can be attributed to their weak metallic bonding, which is primarily due to the presence of only a single valence electron in each atom. This single valence electron experiences relatively weak forces of attraction to the positively charged metal ions, leading to lower melting and boiling points.

Topic: Chemistry, s Block Elements, NEET
What is the primary reason for the low solubility of haloalkanes in water?

Options:
A Strong hydrogen bonding with water
B Weak attractions between haloalkanes and water
C High energy content of haloalkanes
D Strong intermolecular attractions with water

The correct answer is:
Weak attractions between haloalkanes and water

Solution:
The solubility of haloalkanes in water is low because the attractions between haloalkanes and water are not as strong as the original hydrogen bonds in water.

Topic: Chemistry, Haloalkanes and Haloarenes, NEET
What is the primary reason for the lower pressure exerted by real gases compared to ideal gases at high pressures?

Options:
A The higher temperature of real gases
B The difference in the molecular composition of real gases
C The effect of molecular interactions due to molecular attractive forces
D The lower number of gas molecules in real gases

The correct answer is:
The effect of molecular interactions due to molecular attractive forces

Solution:
The lower pressure exerted by real gases at high pressures is due to the effect of molecular interactions resulting from molecular attractive forces.

Topic: Chemistry, States of Matter, NEET
What is the primary reason for the need for highly sophisticated and costly equipment in the synthesis and characterization of new elements?

Options:
A To make the discovery process easier.
B To ensure the safety of scientists.
C Because new elements are highly stable.
D Because the new elements are highly unstable and require specialized equipment.

The correct answer is:
Because the new elements are highly unstable and require specialized equipment.

Solution:
The new elements with very high atomic numbers are so unstable that only minute quantities, sometimes only a few atoms of them are obtained. Their synthesis and characterisation, therefore, require highly sophisticated costly equipment and laboratory."

Topic: Chemistry, Classification of Elements and Periodicity in Properties, NEET
What is the primary reason for the non-polar and hydrophobic nature of greasy substances like those in dry cleaning?

Options:
A Presence of hydrogen bonding
B High electronegativity of carbon atoms
C Non-polar nature of greasy substances
D Ionic nature of greasy substances

The correct answer is:
Non-polar nature of greasy substances

Solution:
Greasy substances, which are mixtures of higher alkanes, are non-polar and hydrophobic in nature due to the absence of significant charge separation and the presence of weak van der Waals forces.

Topic: Chemistry, Hydrocarbons, NEET
What is the primary reason for the peroxide effect's reactivity with unsymmetrical alkenes?

Options:
A The unsymmetrical alkene's molecular weight
B The geometry of the alkene molecule
C The presence of carbon-carbon double bonds
D The formation of free radicals in the reaction

The correct answer is:
The formation of free radicals in the reaction

Solution:
The primary reason for the peroxide effect's reactivity with unsymmetrical alkenes is the formation of free radicals during the reaction.

Topic: Chemistry, Hydrocarbons, NEET
What is the primary reason for the presence of lead and selenium in the anode mud during the electrolytic refining of copper?

Options:
A They are intentionally added to enhance the refining process.
B They are impurities in the original copper ore.
C They are by-products of the electrorefining process.
D They are added to increase the conductivity of the electrolyte.

The correct answer is:
They are impurities in the original copper ore.

Solution:
Correct Option is : (B)
They are impurities in the original copper ore.

Topic: Chemistry, General Principles and Processes of Isolation of Metals, NEET
What is the primary reason for the resonance theory to be applied in explaining the structure of certain molecules?

Options:
A To determine the molecular weight
B To predict the color of the molecule
C To account for the inability to represent the molecule by a single Lewis structure
D To calculate the density of the molecule

The correct answer is:
To account for the inability to represent the molecule by a single Lewis structure

Solution:
Resonance theory is applied when the behavior of certain molecules cannot be explained by a single Lewis structure.

Topic: Chemistry, General Organic Chemistry, NEET
What is the primary reason for the rigidity of solids?

Options:
A High temperature
B Low density
C Fixed positions of molecules
D Free movement of molecules

The correct answer is:
Fixed positions of molecules

Solution:
The primary reason for the rigidity of solids is the fixed positions of molecules, as stated in the paragraph.

Topic: Chemistry, Solid State, NEET
What is the primary reason for the slow electrophilic substitution reactions in haloarenes compared to benzene?

Options:
A Decreased electron density at ortho- and para- positions
B Increased electron density at ortho- and para- positions
C Presence of an electron-donating group
D Absence of a halogen atom

The correct answer is:
Decreased electron density at ortho- and para- positions

Solution:
Due to resonance, electron density increases more at ortho- and para- positions in benzene, leading to slower electrophilic substitution reactions in haloarenes.

Topic: Chemistry, Haloalkanes and Haloarenes, NEET
What is the primary reason for the solubility of alcohols and phenols in water?

Options:
A Formation of covalent bonds with water
B Formation of ionic bonds with water
C Ability to form hydrogen bonds with water
D Decreased size of alkyl/aryl groups

The correct answer is:
Ability to form hydrogen bonds with water

Solution:
Solubility in water is due to the ability of alcohols and phenols to form hydrogen bonds with water molecules.

Topic: Chemistry, Alcohols Phenols and Ethers, NEET
What is the primary reason for the stability of the -2 oxidation state of oxygen?

Options:
A Low electronegativity
B High electronegativity
C Neutral electron configuration
D High atomic radius

The correct answer is:
High electronegativity

Solution:
The paragraph indicates that oxygen's high electronegativity results in the stability of the -2 oxidation state.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
What is the primary reason for the unpleasant odour of aliphatic carboxylic acids?

Options:
A Formation of esters
B Formation of hydrogen bonds
C Weak dipole-dipole interactions
D Strong dipole-dipole interactions

The correct answer is:
Formation of esters

Solution:
The unpleasant odour of aliphatic carboxylic acids is often associated with the formation of esters.

Topic: Chemistry, Aldehydes, Ketones and Carboxylic Acids, NEET
What is the primary reason for using the flame test for calcium, strontium, and barium?

Options:
A To observe the temperature of the flame
B To detect their characteristic colors in qualitative analysis
C To estimate their atomic masses
D To measure their ionization energies

The correct answer is:
To detect their characteristic colors in qualitative analysis

Solution:
The flame test is used to detect the characteristic colors (brick red, crimson, apple green) of calcium, strontium, and barium, which aids in qualitative analysis.

Topic: Chemistry, s Block Elements, NEET
What is the primary reason why a microwave oven heats up a food item containing water molecules most efficiently?

Options:
A Direct conduction of heat from the microwave source
B High radiation emission of microwaves in the oven
C Thermal convection within the food item
D Frequency of the microwave matches the resonant frequency of water molecules

The correct answer is:
Frequency of the microwave matches the resonant frequency of water molecules

Solution:
Correct Option is : (D)
Frequency of the microwave matches the resonant frequency of water molecules

Topic: Chemistry, Electromagnetic Waves, NEET
What is the primary respiratory organ of arthropods?

Options:
A Lungs
B Gills
C Book lungs
D Tracheal system

The correct answer is:
Tracheal system

Solution:
Arthropods have a tracheal system as the primary respiratory organ.

Topic: Biology, Animal Kingdom, NEET
What is the primary response when encountering a pathogen for the first time called?

Options:
A Humoral immune response
B Cell-mediated immune response
C Low-intensity response
D High-intensity response

The correct answer is:
Low-intensity response

Solution:
The primary response when encountering a pathogen for the first time is called the primary response and is of low intensity.

Topic: Biology, Human Health and Diseases, NEET
What is the primary result of the overlap between the sp hybridised orbitals and the 2p-orbitals of chlorine?

Options:
A Formation of pi bonds
B Formation of sigma bonds
C Formation of nonpolar bonds
D Formation of unstable compounds

The correct answer is:
Formation of sigma bonds

Solution:
The overlap between the sp hybridised orbitals and the 2p-orbitals of chlorine results in the formation of two Be-Cl sigma bonds

Topic: Chemistry, Chemical Bonding and Molecular Structure, NEET
What is the primary role of a catalyst in a chemical reaction?

Options:
A Increasing the equilibrium constant
B Lowering the activation energy for the forward reaction
C Changing the reactants into products
D Affecting the equilibrium composition

The correct answer is:
Lowering the activation energy for the forward reaction

Solution:
A catalyst lowers the activation energy for the forward reaction.

Topic: Chemistry, Chemical Equilibrium, NEET
What is the primary role of a Lewis acid in the halogenation of arenes?

Options:
A Acting as a reducing agent
B Providing color to the reaction mixture
C Acting as a catalyst to facilitate the reaction
D Enhancing the odor of the products

The correct answer is:
Acting as a catalyst to facilitate the reaction

Solution:
Lewis acids in the halogenation of arenes act as catalysts, facilitating the reaction by promoting the formation of reactive intermediates.

Topic: Chemistry, Hydrocarbons, NEET
What is the primary role of aerobic bacteria in water?

Options:
A Producing foul-smelling chemicals
B Depleting dissolved oxygen levels
C Enhancing water quality
D Promoting the growth of algae

The correct answer is:
Enhancing water quality

Solution:
Aerobic bacteria play a crucial role in enhancing water quality by breaking down organic matter.

Topic: Chemistry, Environmental Chemistry, NEET
What is the primary role of bacteria in water with organic matter?

Options:
A They increase the oxygen concentration in water.
B They consume dissolved oxygen in water.
C They convert organic matter into oxygen.
D They have no impact on water quality.

The correct answer is:
They consume dissolved oxygen in water.

Solution:
Bacteria in water decompose organic matter and, in the process, consume the dissolved oxygen in the water, which can lead to a reduction in oxygen levels, affecting aquatic life.

Topic: Chemistry, Environmental Chemistry, NEET
What is the primary role of common names in organic chemistry?

Options:
A To simplify the identification of isomers
B To make the names sound more scientific
C To assign names based on molecular weight
D To provide shorter and more practical names

The correct answer is:
To provide shorter and more practical names

Solution:
Common names are useful for providing shorter and more practical names.

Topic: Chemistry, General Organic Chemistry, NEET
What is the primary role of concentrated sulphuric acid in drying wet gases?

Options:
A As a dehydrating agent
B As an acid catalyst
C As a source of SO2
D As an oxidizing agent

The correct answer is:
As a dehydrating agent

Solution:
Concentrated sulphuric acid is primarily used as a dehydrating agent in drying wet gases.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
What is the primary role of electrons placed in a bonding molecular orbital?

Options:
A To increase the repulsion between nuclei
B To induce destructive interference
C To destabilize the molecule
D To hold the nuclei together and stabilize the molecule

The correct answer is:
To hold the nuclei together and stabilize the molecule

Solution:
Electrons placed in a bonding molecular orbital primarily hold the nuclei together and stabilize the molecule.

Topic: Chemistry, Chemical Bonding and Molecular Structure, NEET