datavorous/entrance-exam-dataset huggingface dataset:
Aspirin can be prepared by the reaction of

Options:
A
Salicyldehyde with acetic anhydride in presence of $\mathrm{H}_2 \mathrm{SO}_4$

B
Salicylic acid with methanol in presence of $\mathrm{H}_2 \mathrm{SO}_4$

C
Salicylic acid with acetic anhydride in presence of $\mathrm{H}_2 \mathrm{SO}_4$

D
Cinnamic acid with acetic anhydride in presence of $\mathrm{H}_2 \mathrm{SO}_4$

The correct answer is:
Salicylic acid with acetic anhydride in presence of $\mathrm{H}_2 \mathrm{SO}_4$

Solution:
Asprin is prepared by reaction of salicylic acid with acetic anhydride in presence of $\mathrm{H}_2 \mathrm{SO}_4$

Topic: Chemistry, Chemistry in Everyday Life, JEE Main, JEE Main 2012 (19 May Online)
Aspirin is an acetylation product of

Options:
A p-dihydroxy benzene
B m-hydroxy benzoic acid
C o-dihydroxy benzene and salicylic acid both
D o-hydroxy benzoic acid

The correct answer is:
o-hydroxy benzoic acid

Solution:

Topic: Chemistry, Chemistry in Everyday Life, JEE Main
Aspirin is known as:

Options:
A
Acetyl salicylic acid

B
Phenyl salicylate

C
Acetyl salicylate

D
Methyl salicylic acid

The correct answer is:
Acetyl salicylic acid

Solution:
Acetyl salicylic acid

Topic: Chemistry, Chemistry in Everyday Life, JEE Main, JEE Main 2012 (Offline)
Assertion (A) a, b, c, d are position vectors of 4 points such that $2 \mathbf{a}-3 \mathbf{b}+7 \mathbf{c}-6 \mathbf{d}=0 \Rightarrow$ $\mathbf{a}, \mathbf{b}, \mathbf{c}, \mathbf{d}$ are coplanar.
Reason (R) Vector equation of the plane passing through three points whose position vectors are $\mathbf{a}, \mathbf{b}, \mathbf{c}$ is $\mathbf{r}=(1-x-y) \mathbf{a}+x \mathbf{b}+y \mathbf{c}$.
Which of the following is true?

Options:
A Both $(A)$ and $(R)$ are true and $(R)$ is the correct explanation of (A)
B Both $(A)$
and (R) are true, but (R) is not the correct explanation of $(A)$
C $(A)$ is true, but $(R)$ is false
D $(A)$ is false, but $(R)$ is true

The correct answer is:
Both $(A)$ and $(R)$ are true and $(R)$ is the correct explanation of (A)

Solution:
Vector equation of plane passing through three non-collinear points is
$$
\mathbf{r}=(1-x-y) \mathbf{a}+x \mathbf{b}+y \mathbf{c}
$$
If $a, b, c, d$ are coplanar, then $\mathbf{d}$ should satisfy
Eq. (i) for some $x, y$
$$
\mathbf{d}=(1-x-y) \mathbf{a}+x(\mathbf{b})+y \mathbf{c}
$$
Given, $\quad 2 \mathbf{a}-3 \mathbf{b}+7 \mathbf{c}=6 \mathbf{d}$
$\Rightarrow \quad \frac{2 \mathbf{a}-3 \mathbf{b}+7 \mathbf{c}}{6}=\mathbf{d}$
By substituting the value of $\mathbf{d}$ in Eq. (i), we get
$$
\frac{2 \mathbf{a}-3 \mathbf{b}+7 \mathbf{c}}{6}=(1-x-y) \mathbf{a}+x(\mathbf{b})+y \mathbf{c}
$$
$$
\Rightarrow \quad 1-x-y=\frac{1}{3}
$$
$$
x=-\frac{1}{2}, y=\frac{7}{6}
$$
Substituting value of $x$ and $y$ in Eq. (ii)
$1-\left(-\frac{1}{2}\right)-\frac{7}{6}=\frac{1}{3}$ satisfy the Eq.(ii)
Hence, $\mathbf{b}$ lie on plane $\Rightarrow \mathbf{a}, \mathbf{b}, \mathbf{c}, \mathbf{d}$ are coplanar Hence, $A$ is correct, $R$ is correct and $R$ is correct explanation for $A$.

Topic: Mathematics, Three Dimensional Geometry, JEE Main
Assertion (A) : A current of $96.5 \mathrm{~A}$ is passed into aqueous $\mathrm{AgNO}_3$ solution for $100 \mathrm{~s}$. The weight of silver deposited is $10.8 \mathrm{~g}$ (At. wt. of $\mathrm{Ag}=108)$Reason (R) : The mass of a substance deposited during the electrolysis of an electrolyte is inversely proportional to the quantity of electricity passing through the electrolyte.
The correct answer is :

Options:
A Both (A) and (R) are true and (R) is the correct explanation of (A)
B Both (A) and (R) are true but (R) is not the correct explanation of (A)
C (A) is true but (R) is false
D (A) is false but (R) is true

The correct answer is:
(A) is true but (R) is false

Solution:
$i=96.5 \mathrm{~A}, t=100 \mathrm{~s}$
$w=108$
$Q=i t$
$Q=96.5 \times 100=9650 \mathrm{C}$
$\because 96500$ coulomb deposited wt. of $\mathrm{Ag}=108 \mathrm{~g}$
$\therefore 9650$ coulomb deposited wt. of Ag
$=\frac{108 \times 9650}{96500}$
So, statement $\mathbf{A}$ is true but $\mathbf{R}$ is false. $\mathbf{R}$ is false because mass of substance deposited is directly proportional to the quantity of electricity.

Topic: Chemistry, Electrochemistry, JEE Main
Assertion (A): A magnetic needle free to rotate in a vertical plane, orients itself (with its axis) vertical at the poles of the earth.
Reason (R): At the poles of the earth the horizontal component of earth's magnetic field will be zero.
Select the most appropriate answer from the options given below:

Options:
A Both $A$ and $R$ are true and $R$ is the correct explanation of $A$
B Both $A$ and $R$ are true but $R$ is not the correct explanation of $A$.
C A is true but $R$ is false.
D $A$ is false and $R$ is also false.

The correct answer is:
Both $A$ and $R$ are true and $R$ is the correct explanation of $A$

Solution:
$\rightarrow$ At the poles of the earth, the angle of dip is $90^{\circ}$.
$\therefore$ the Components of ear th's magnetic field $\left(\mathrm{B}_{\mathrm{E}}\right)$ at the poles are:
$\rightarrow$ Vertical component $V=B_E \sin \left(90^{\circ}\right)$
$V=B_E$
$\rightarrow$ Horizontal component $\mathrm{H}=\mathrm{B}_{\mathrm{E}} \cos \left(90^{\circ}\right)$
$\mathrm{H}=0$
$\rightarrow$ Thus a magnetic needle free to rotate will orient vertically along the poles of the earth as the horizontal component of the earth's magnetic field is zero
Hence, the correct option is (1).

Topic: Physics, Magnetic Properties of Matter, JEE Main
Assertion (A)
Angular speed, linear speed and kinetic energy change with time but angular momentum remains constant for a planet orbiting the sun.
Reason (R) Angular momentum is constant as no torque acts on the planet.

Options:
A Both $\mathrm{A}$ and $\mathrm{R}$ are true and $\mathrm{R}$ is a correct explanation for $A$.
B Both $\mathrm{A}$ and $\mathrm{R}$ are true but $\mathrm{R}$ is not a correct explanation for $A$.
C $A$ is true, $R$ is false.
D $A$ is false, $R$ is true.

The correct answer is:
Both $\mathrm{A}$ and $\mathrm{R}$ are true and $\mathrm{R}$ is a correct explanation for $A$.

Solution:
As we know that, Torque is the moment of force and torque $(\tau)=\mathbf{r} \times \mathbf{F}$ where, $\mathbf{r}$ is distance between axis of rotation and force $(F)$.
Also, $\tau=\frac{d L}{d t}$
and since, in space there is no external torque is applied so, $\tau=0$
$$
\therefore \quad \Delta L=0=\text { constant }
$$
Hence, Assertion (A) and Reason (R) both are true and Reason (R) is the correct explanation of Assertion (A).

Topic: Physics, Gravitation, AP EAMCET, AP EAMCET 2021 (23 Aug Shift 1)
Assertion (A) Electromagnetic force is enormously strong as compared to gravitational force. Yet, gravity dominates in the large-scale phenomena (e.g. formation of galaxies).
Reason $(R)$ Existence of positive and negative charges make matter mostly electrically neutral.
Which of the following is true?

Options:
A Both $(A)$ and $(R)$ are true and $(R)$ is the correct explanation of $(A)$
B Both $(A)$ and $(R)$ are true, but $(R)$ is not the correct explanation of (A)
C (A) is true, but $(R)$ is false
D (A) is false, but $(R)$ is true

The correct answer is:
Both $(A)$ and $(R)$ are true and $(R)$ is the correct explanation of $(A)$

Solution:
Both A and $\mathrm{R}$ true and $\mathrm{R}$ is the correct explanation of A.
"Although the electromagnetic force is far stronger than gravity, it tends to cancel itself out within large objects, so over the largest distances (on the scale of planets and galaxies), gravity is the dominant force."

Topic: Physics, Electrostatics, JEE Main
Assertion (A) Energy per unit volume and angular momentum can be added dimensionally.
Reason (R) Physical quantities having same dimensions can be added or subtracted.

Options:
A Both (A) and (R) are true and (R) is the correct explanation of (A)
B Both (A) and (R) are true but (R) is not the correct explanation of (A)
C (A) is true but (R) is false
D (A) is false but (R) is true

The correct answer is:
(A) is false but (R) is true

Solution:
The units of energy per unit volume is $\mathrm{J} / \mathrm{m}^3$ or $\mathrm{kg} / \mathrm{m}-\mathrm{s}^2$ and that for angular momentum is $\mathrm{kg}-\mathrm{m}^2 / \mathrm{s}$.
Since, they are not dimensionally equal, they cannot be added, so the Assertion (A) is false. Only those physical quantities that have same dimensions can be added or subtracted, so Reason (R) is true.
Hence, the correct option is $(\mathrm{d})$.

Topic: Physics, Units and Dimensions, JEE Main
Assertion A : Enol form of acetone CH3COCH3 exists in <0.1% quantity. However, the enol form of acetyl acetone CH3COCH2OCCH3 exists in approximately 15%quantity.

Reason R : enol form of acetyl acetone is stabilized by intramolecular hydrogen bonding, which is not possible in enol form of acetone.

Choose the correct statement:

Options:
A A is false but R is true
B Both A and R are true and R is the correct explanation of A
C Both A and R are true but R is not the correct explanation of A
D A is true but R is false

The correct answer is:
Both A and R are true and R is the correct explanation of A

Solution:
Acetyl acetone in enol form have intramolecular H-bonding, which is absent in acetone.

enol form of Acetyl acetone is stabilised by conjugation and by intramolecular H-bonding.

enol form of acetone is very less <0.1%

Topic: Chemistry, General Organic Chemistry, JEE Main, JEE Main 2021 (16 Mar Shift 1)
Assertion : A gamete may carry either of the traits but not both.
Reason : This is Mendel's second law or law of independent assortment.

Options:
A If both assertion and reason are true and reason is the correct explanation of assertion
B If both assertion and reason are true but reason is not the correct explanation of assertion
C If assertion is true but reason is false
D If both assertion and reason are false.

The correct answer is:
If assertion is true but reason is false

Solution:
The law of segregation states that the two alleles controlling each character maintain indentity in the organism but during the formation of gametes or spores by meiosis move apart due to separation of the homologous chromosomes which bear them, so that each gamete or spore receives only one allele of each character on random basis. Since the gametes or spores possess one allele of each character, they are always pure. The law of segregation is, therefore, also called the law of purity of gametes/spores. Mendel's second law or the law of independent assortment states that the alleles of different characters located in different pairs of homologous chromosomes are independent of one another in their segregation during gamete formation and in coming together into the offspring by fertilization, both processes occurring randomly.

Topic: Biology, Principles of Inheritance and Variation, AIIMS, AIIMS 2009
Assertion : A hollow metallic closed container maintained at a uniform temperature can act as a source of black body radiation.
Reason : All metals act as black bodies.

Options:
A If both assertion and reason are true and reason is the correct explanation of assertion
B If both assertion and reason are true but reason is not the correct explanation of assertion
C If assertion is true but reason is false
D If both assertion and reason are false.

The correct answer is:
If both assertion and reason are false.

Solution:
A hollow metallic container with a small orifice and coated with lamp black inside is taken as a source of black-body radiation when it is heated. A closed container cannot act as a source of blackbody because it cannot absorb all radiations.
All metals are not black bodies. A black body is described above. It is the hole that absorbs and emits the radiation, which is treated as a black body and not even the whole container. Assertion is only partially correct.

Topic: Physics, Thermal Properties of Matter, AIIMS, AIIMS 2007
Assertion : A hollow metallic closed container with small opening maintained at a high temperature can act as a source of black body radiation.
Reason : All metals act as black body radiator.

Options:
A If both assertion and reason are true and reason is the correct explanation of assertion.
B Ifboth assertion and reason are true but reason is not the correct explanation of assertion.
C If assertion is true but reason is false.
D If both assertion and reason are false.

The correct answer is:
If assertion is true but reason is false.

Solution:
No Solution Available

Topic: Physics, Thermal Properties of Matter, AIIMS, AIIMS 2015
Assertion A: Hydrolysis of an alkyl chloride is a slow reaction but in the presence of NaI, the rate of hydrolysis increases.

Reason R: I- is a good nucleophile as well as a good leaving group.

In the light of the above statements, choose the correct answer from the options given below.

Options:
A A is false but R is true
B A is true but R is false
C Both A and R are true and R is the correct explanation of A
D Both A and R are true and R is not the correct explanation of A

The correct answer is:
Both A and R are true and R is the correct explanation of A

Solution:
Iodide ion is a powerful nucleophile and hence reacts rapidly with RCl to form RI. Further because I− ion is a better leaving group than Cl− ion, therefore , RI is more rapidly hydrolysed than RCl to form ROH.

Topic: Chemistry, Haloalkanes and Haloarenes, JEE Main, JEE Main 2023 (24 Jan Shift 1)
Assertion (A) : I- Bromopentane reacts with $\mathrm{AgCN}$ to give pentylisocyanide
Reason (R): $\mathrm{AgCN}$ is mainly ionic in nature

Options:
A A is true, $\mathrm{R}$ is true and $\mathrm{R}$ is correct explanation of $\mathrm{A}$
B $\mathrm{A}$ is true, $\mathrm{R}$ is true but $\mathrm{R}$ is not correct explanation of A
C $A$ is true, $R$ is false
D A is false, $R$ is true

The correct answer is:
$A$ is true, $R$ is false

Solution:
$\mathrm{AgCN}$ is covalent in nature. Thats why haloalkane produces isocyanide compound with $\mathrm{AgCN}$ and cyanide compound with $\mathrm{KCN}$.

Topic: Chemistry, Haloalkanes and Haloarenes, AP EAMCET, AP EAMCET 2022 (05 Jul Shift 2)
Assertion A: If A, B, C, D are four points on a semi-circular arc with a centre at O such that |AB→|=|BC→|=|CD→|. Then, AB→+AC→+AD→=4AO→+OB→+OC→

Reason R: Polygon law of vector addition yields AB→+BC→+CD→+AD→=2AO→

In the light of the above statements, choose the most appropriate answer from the options given below.

Options:
A A is correct but R is not correct.
B A is not correct but R is correct.
C Both A and R are correct and R is the correct explanation of A.
D Both A and R are correct but R is not the correct explanation of A.

The correct answer is:
Both A and R are correct but R is not the correct explanation of A.

Solution:
Polygon law is applicable in both but the equation given in the reason is not useful in explaining the assertion.

Topic: Physics, Mathematics in Physics, JEE Main, JEE Main 2021 (27 Jul Shift 1)
Assertion A: If in five complete rotations of the circular scale, the distance travelled on the main scale of the screw gauge is 5 mm and there are 50 total divisions on a circular scale, then the least count is 0.001 cm.

Reason R:
Least Count = Pitch Total divisions on circular scale
In the light of the above statements, choose the most appropriate answer from the options given below.

Options:
A A is not correct but R is correct.
B Both A and R are correct and R is the correct explanation of A.
C A is correct but R is not correct.
D Both A and R are correct and R is NOT the correct explanation of A.

The correct answer is:
A is not correct but R is correct.

Solution:
Least count = Pitch total division on circular scale
In 5 revolution, distance travel, 5 mm.

In 1 revolution, it will travel 1 mm.
So the least count =150=0.02

Topic: Physics, Experimental Physics, JEE Main, JEE Main 2021 (27 Jul Shift 1)
Assertion (A): In a elastic collision of two billiard balls,
both kinetic energy and linear momentum remain conserved.
Reason (R): During the collision of the balls, as the
collision is elastic there is no exchange of energy.
Therefore, both energy and momentum are conserved.
The correct option among the following is

Options:
A (A) is true, (R) is true and (R) is the correct
explanation for (A)
B (A) is true, (R) is true but (R) is not the correct
explanation for (A)
C (A) is true but (R) is false
D (A) is false but (R) is true

The correct answer is:
(A) is true but (R) is false

Solution:
No solution. Refer to answer key.

Topic: Physics, Center of Mass Momentum and Collision, TS EAMCET, TS EAMCET 2022 (19 Jul Shift 1)
Assertion (A): In a region of constant potential, the electric field is zero and there can be no charge inside the region.

Reason (R): According to Gauss law. charge inside the region should be zero if electric field is zero.

Options:
A Both (A) and (R) are true: (R) is correct explanation of (A)
B Both (A) and (R) are true; (R) is not correct explanation of (A)
C (A) is true, (R) is false
D (A) is false, (R) is true

The correct answer is:
Both (A) and (R) are true; (R) is not correct explanation of (A)

Solution:
For Assertion,

Potential difference is given by dV=-E→·dr→, If E→ is zero, the potential will remain constant.

For Reason,

If in a region electric field is zero, net flux through any closed surface in that region will be zero. Therefore, if electric field is zero, according to Gauss's law the charge inside the region should be zero. Therefore, reason statement is correct, but it does not explain why the potential is constant.

Topic: Physics, Electrostatics, AP EAMCET, AP EAMCET 2022 (04 Jul Shift 2)
Assertion(A) In an elastic collision of two billiard balls, the total KE is conserved during the short time of collision of the balls
(i.e., when they are in contact).Reason(R) Energy spent against friction does not follow the law of conservation of energy.
Codes

Options:
A Both A and R are true and R is a correct explanation for A.
B Both A and R are true but R is not a correct explanation for A.
C A is true but R is false.
D Both A and R is false.

The correct answer is:
Both A and R is false.

Solution:
In an elastic collision of two billiard balls, there is deformation in shape of balls momentarily. During the collision potential energy
increases due to deformation of balls and kinetic energy decreases. Hence, total energy remains constant but kinetic energy is not conserved.
Law of conservation of energy always applies, in
every case.
Thus, both Assertion and Reason are false.

Topic: Physics, Center of Mass Momentum and Collision, AP EAMCET, AP EAMCET 2021 (25 Aug Shift 2)
Assertion : A particle strikes head-on with another stationary particle such that the first particle comes to rest after collision. The collision should necessarily be elastic.
Reason : In elastic collision, there is a loss of momentum of the system of the particles.

Options:
A If both assertion and reason are true and reason is the correct explanation of assertion.
B If both assertion and reason are true but reason is not the correct explanation of assertion.
C If assertion is true but reason is false.
D If both assertion and reason are false.

The correct answer is:
If both assertion and reason are false.

Solution:
Momentum of a system remains conserved in any kind of collision.

Topic: Physics, Center of Mass Momentum and Collision, AIIMS, AIIMS 2017
Assertion A: Product of Pressure P and time t has the same dimension as that of coefficient of viscosity.

Reason: Coefficient of viscosity = Force Velocity gradient

Options:
A Both A and R true, and R is correct explanation of A.
B Both A and R are true but R is NOT the correct explanation of A.
C A is true but R is false.
D A is false but R is true.

The correct answer is:
A is true but R is false.

Solution:
Viscous force is given by F=ηAdvdt, here, A is area and dvdt is velocity gradient.

Thus, η=FAdvdt.

Now, Pt=FAt=ηdvdtt

Then, Pt=ML-1T-1=η

Thus, assertion is true but reason is false.

Topic: Physics, Units and Dimensions, JEE Main, JEE Main 2022 (28 Jun Shift 1)
Assertion: A ray incident along normal to the mirror retraces its path.
Reason: In reflection, angle of incidence is always equal to angle of reflection.

Options:
A If both Assertion and Reason are true and the Reason is correct explanation of the Assertion.
B If both Assertion and Reason are true but Reason is not explanation of the Assertion.
C If Assertion is true but the Reason is false.
D If Assertion is false but Reason is true.

The correct answer is:
If both Assertion and Reason are true and the Reason is correct explanation of the Assertion.

Solution:
The incident is along with the normal means the angle of incidence is i=90°, so from laws of reflection the angle of incidence is equal to angle of reflection, the angle of reflection will be i=r=90°; means the reflected ray retraces the same path, which conclude both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.

Topic: Physics, Ray Optics, JEE Main
Assertion (A) Si and GaAs are the preferred materials for solar cells.
Reason (R) Both these materials have energy band gaps much below the energy level corresponding to the maximum solar irradiance ln the solar spectrum.
The correct answer is

Options:
A $(A)$ is correct but $(R)$ is incorrect.
B Both (A) and (R) are correct and (R) is the correct explanation of (A).
C Both $(A)$ and $(R)$ are correct but $(R)$ is not the correct explanation of (A).
D Both (A) and (R) are incorrect.

The correct answer is:
$(A)$ is correct but $(R)$ is incorrect.

Solution:
Key Idea The energy band gap of Si is $1.14 \mathrm{eV}$ and GaAs is $1.42 \mathrm{eV}$.
Both Si and GaAs are used to make solar cells. In visible spectrum, energy is vary from about $3 \mathrm{eV}$ on the violet side to $1.5 \mathrm{eV}$ on red side, so visible light can make solar energy.
But radiowaves, microwaves and Infrared waves has less photon energy than the band gap of Si and GaAs.
Hence, the assertion is correct but reason is wrong. Therefore, the correct option is (a).

Topic: Physics, Semiconductors, JEE Main
Assertion : A solution containing a mixture of acetic acid and sodium acetate maintains a constant value of $\mathrm{pH}$ on addition of small amounts of acid or alkali.
Reason : A solution containing a mixture of acetic acid and sodium acetate acts as a buffer solution around $\mathrm{pH}$ of $4.75$.

Options:
A
If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

B
If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

C
If the Assertion is correct but Reason is incorrect.

D
If the Assertion is incorrect but the Reason is correct.

The correct answer is:
If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

Solution:
Both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

Topic: Chemistry, Equilibrium
Assertion (A) The colour of radiation does not change on passing through different media.
Reason (R) The media do not absorb or emit colours.

Options:
A Both $A$ and $R$ are true and $R$ is a correct explanation for $A$.
B Both $\mathrm{A}$ and $\mathrm{R}$ are true but $\mathrm{R}$ is not a correct explanation for $\mathrm{A}$.
C $A$ is true but $R$ is false.
D A is false but $R$ is true.

The correct answer is:
$A$ is true but $R$ is false.

Solution:
The colour of radiation does not change on passing through different media. This is because, when light radiation passes through different media, only wavelength and speed changes, but frequency remains same and colour of light radiation depends only on frequency.
Hence, Assertion (A) is true.
"The media do not absorb or emit colours" this statement is wrong. Because the absorption or emission of colours of radiation depends only on the nature of medium.
Hence, Reason is false.

Topic: Physics, Dual Nature of Matter, AP EAMCET, AP EAMCET 2021 (23 Aug Shift 2)