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JEE Main 2025 Jan 28 Shift 1 β€” Question Paper

75 questions

Mathematics

Q1JEE Main 2025 Jan 28 Shift 1Sets, Relations and FunctionsEasy

The relation R={(x,y):x,y∈Z and x+y is even}R = \{(x, y) : x, y \in \mathbb{Z} \text{ and } x + y \text{ is even}\} is:

  1. A

    reflexive and transitive but not symmetric

  2. B

    reflexive and symmetric but not transitive

  3. C

    symmetric and transitive but not reflexive

  4. D

    an equivalence relation

Show answer

Correct option: D

Q2JEE Main 2025 Jan 28 Shift 1Sets, Relations and FunctionsMedium

If f(x)=2x2x+2f(x) = \frac{2^x}{2^x + \sqrt{2}}, x∈Rx \in \mathbb{R}, then βˆ‘k=181f(k82)\sum_{k=1}^{81} f\left(\frac{k}{82}\right) is equal to

  1. A

    4141

  2. B

    812\frac{81}{2}

  3. C

    8282

  4. D

    81281\sqrt{2}

Show answer

Correct option: B

Q3JEE Main 2025 Jan 28 Shift 1Complex NumbersMedium

Let O be the origin, the point A be z1=3+22 iz_1 = \sqrt{3} + 2\sqrt{2}\,i, the point B(z2)(z_2) be such that 3β€‰βˆ£z2∣=∣z1∣\sqrt{3}\,|z_2| = |z_1| and arg⁑(z2)=arg⁑(z1)+Ο€6\arg(z_2) = \arg(z_1) + \frac{\pi}{6}. Then

  1. A

    ABO is an obtuse angled isosceles triangle

  2. B

    area of triangle ABO is 114\frac{11}{4}

  3. C

    area of triangle ABO is 113\frac{11}{\sqrt{3}}

  4. D

    ABO is a scalene triangle

Show answer

Correct option: A

Q4JEE Main 2025 Jan 28 Shift 1Quadratic EquationsMedium

The sum of the squares of all the roots of the equation x2+∣2xβˆ’3βˆ£βˆ’4=0x^2 + |2x - 3| - 4 = 0 is

  1. A

    6(2βˆ’2)6(2 - \sqrt{2})

  2. B

    3(2βˆ’2)3(2 - \sqrt{2})

  3. C

    6(3βˆ’2)6(3 - \sqrt{2})

  4. D

    3(3βˆ’2)3(3 - \sqrt{2})

Show answer

Correct option: A

Q5JEE Main 2025 Jan 28 Shift 1Sequences and SeriesMedium

Let <an><a_n> be a sequence such that a0=0a_0 = 0, a1=12a_1 = \frac{1}{2} and 2an+2=5an+1βˆ’3an2a_{n+2} = 5a_{n+1} - 3a_n, n=0,1,2,3,…n = 0, 1, 2, 3, \ldots. Then βˆ‘k=1100ak\sum_{k=1}^{100} a_k is equal to

  1. A

    3a99+1003a_{99} + 100

  2. B

    3a99βˆ’1003a_{99} - 100

  3. C

    3a100+1003a_{100} + 100

  4. D

    3a100βˆ’1003a_{100} - 100

Show answer

Correct option: D

Q6JEE Main 2025 Jan 28 Shift 1Sequences and SeriesMedium

Let TrT_r be the rthr^{\text{th}} term of an A.P. If for some mm, Tm=125T_m = \frac{1}{25}, T25=120T_{25} = \frac{1}{20}, and 20βˆ‘r=125Tr=1320\sum_{r=1}^{25} T_r = 13, then 5mβˆ‘r=m2mTr5m \sum_{r=m}^{2m} T_r is equal to

  1. A

    9898

  2. B

    112112

  3. C

    126126

  4. D

    142142

Show answer

Correct option: C

Q7JEE Main 2025 Jan 28 Shift 1Permutations and CombinationsMedium

The number of different 5 digit numbers greater than 50000 that can be formed using the digits 0, 1, 2, 3, 4, 5, 6, 7, such that the sum of their first and last digits should not be more than 8, is

  1. A

    46074607

  2. B

    46084608

  3. C

    57195719

  4. D

    57205720

Show answer

Correct option: A

Q8JEE Main 2025 Jan 28 Shift 1ProbabilityMedium

Three defective oranges are accidently mixed with seven good ones and on looking at them, it is not possible to differentiate between them. Two oranges are drawn at random from the lot. If xx denote the number of defective oranges, then the variance of xx is

  1. A

    14/2514/25

  2. B

    26/7526/75

  3. C

    28/7528/75

  4. D

    18/2518/25

Show answer

Correct option: C

Q9JEE Main 2025 Jan 28 Shift 1ProbabilityMedium

Two numbers k1k_1 and k2k_2 are randomly chosen from the set of natural numbers. Then the probability that the value of ik1+ik2i^{k_1} + i^{k_2}, (i=βˆ’1)(i = \sqrt{-1}) is non-zero, equals

  1. A

    14\frac{1}{4}

  2. B

    12\frac{1}{2}

  3. C

    34\frac{3}{4}

  4. D

    23\frac{2}{3}

Show answer

Correct option: C

Q10JEE Main 2025 Jan 28 Shift 1Conic SectionsMedium

Let ABCD be a trapezium whose vertices lie on the parabola y2=4xy^2 = 4x. Let the sides AD and BC of the trapezium be parallel to y-axis. If the diagonal AC is of length 254\frac{25}{4} and it passes through the point (1,0)(1, 0), then the area of ABCD is

  1. A

    252\frac{25}{2}

  2. B

    754\frac{75}{4}

  3. C

    758\frac{75}{8}

  4. D

    1258\frac{125}{8}

Show answer

Correct option: B

Q11JEE Main 2025 Jan 28 Shift 1Permutations and CombinationsMedium

Let nCrβˆ’1=28^{n}C_{r-1} = 28, nCr=56^{n}C_{r} = 56 and nCr+1=70^{n}C_{r+1} = 70. Let A (4cos⁑t,4sin⁑t)(4\cos t, 4\sin t), B (2sin⁑t,βˆ’2cos⁑t)(2\sin t, -2\cos t) and C (3rβˆ’n,r2βˆ’nβˆ’1)(3r - n, r^2 - n - 1) be the vertices of a triangle ABC, where tt is a parameter. If (3xβˆ’1)2+(3y)2=Ξ±(3x - 1)^2 + (3y)^2 = \alpha, is the locus of the centroid of triangle ABC, then Ξ±\alpha equals

  1. A

    2020

  2. B

    1818

  3. C

    88

  4. D

    66

Show answer

Correct option: A

Q12JEE Main 2025 Jan 28 Shift 1CirclesMedium

Let the equation of the circle, which touches x-axis at the point (a,0)(a, 0), a>0a > 0 and cuts off an intercept of length bb on y-axis be x2+y2βˆ’Ξ±x+Ξ²y+Ξ³=0x^2 + y^2 - \alpha x + \beta y + \gamma = 0. If the circle lies below x-axis, then the ordered pair (2a,b2)(2a, b^2) is equal to

  1. A

    (Ξ³,Ξ²2βˆ’4Ξ±)(\gamma, \beta^2 - 4\alpha)

  2. B

    (Ξ±,Ξ²2βˆ’4Ξ³)(\alpha, \beta^2 - 4\gamma)

  3. C

    (Ξ±,Ξ²2+4Ξ³)(\alpha, \beta^2 + 4\gamma)

  4. D

    (Ξ³,Ξ²2+4Ξ±)(\gamma, \beta^2 + 4\alpha)

Show answer

Correct option: B

Q13JEE Main 2025 Jan 28 Shift 1Inverse Trigonometric FunctionsMedium

cos⁑(sinβ‘βˆ’135+sinβ‘βˆ’1513+sinβ‘βˆ’13365)\cos\left(\sin^{-1}\frac{3}{5} + \sin^{-1}\frac{5}{13} + \sin^{-1}\frac{33}{65}\right) is equal to:

  1. A

    00

  2. B

    11

  3. C

    3265\frac{32}{65}

  4. D

    3365\frac{33}{65}

Show answer

Correct option: A

Q14JEE Main 2025 Jan 28 Shift 1Three Dimensional GeometryMedium

Let A (x,y,z)(x, y, z) be a point in xyxy-plane, which is equidistant from three points (0,3,2)(0, 3, 2), (2,0,3)(2, 0, 3) and (0,0,1)(0, 0, 1). Let B =(1,4,βˆ’1)= (1, 4, -1) and C =(2,0,βˆ’2)= (2, 0, -2). Then among the statements (S1) : β–³\triangleABC is an isosceles right angled triangle, and (S2) : the area of β–³\triangleABC is 922\frac{9\sqrt{2}}{2},

  1. A

    both are true

  2. B

    both are false

  3. C

    only (S1) is true

  4. D

    only (S2) is true

Show answer

Correct option: C

Q15JEE Main 2025 Jan 28 Shift 1Three Dimensional GeometryMedium

If the image of the point (4,4,3)(4, 4, 3) in the line xβˆ’12=yβˆ’21=zβˆ’13\frac{x-1}{2} = \frac{y-2}{1} = \frac{z-1}{3} is (Ξ±,Ξ²,Ξ³)(\alpha, \beta, \gamma), then Ξ±+Ξ²+Ξ³\alpha + \beta + \gamma is equal to

  1. A

    77

  2. B

    88

  3. C

    99

  4. D

    1212

Show answer

Correct option: C

Q16JEE Main 2025 Jan 28 Shift 1Differentiation and Applications of DerivativesHard

The sum of all local minimum values of the function f(x)={1βˆ’2x,x<βˆ’113(7+2∣x∣),βˆ’1≀x≀21118(xβˆ’4)(xβˆ’5),x>2f(x) = \begin{cases} 1 - 2x, & x < -1 \\ \frac{1}{3}(7 + 2|x|), & -1 \le x \le 2 \\ \frac{11}{18}(x-4)(x-5), & x > 2 \end{cases} is

  1. A

    16772\frac{167}{72}

  2. B

    13172\frac{131}{72}

  3. C

    15772\frac{157}{72}

  4. D

    17172\frac{171}{72}

Show answer

Correct option: C

Q17JEE Main 2025 Jan 28 Shift 1Integral CalculusMedium

The area (in sq. units) of the region {(x,y):0≀y≀2∣x∣+1,0≀y≀x2+1,∣xβˆ£β‰€3}\{(x, y) : 0 \le y \le 2|x| + 1, 0 \le y \le x^2 + 1, |x| \le 3\} is

  1. A

    643\frac{64}{3}

  2. B

    803\frac{80}{3}

  3. C

    323\frac{32}{3}

  4. D

    173\frac{17}{3}

Show answer

Correct option: A

Q18JEE Main 2025 Jan 28 Shift 1Differential EquationsMedium

Let for some function y=f(x)y = f(x), ∫0xt f(t) dt=x2f(x)\int_0^x t\, f(t)\, dt = x^2 f(x), x>0x > 0 and f(2)=3f(2) = 3. Then f(6)f(6) is equal to

  1. A

    11

  2. B

    22

  3. C

    33

  4. D

    66

Show answer

Correct option: A

Q19JEE Main 2025 Jan 28 Shift 1Sets, Relations and FunctionsHard

Let f:Rβ†’Rf : \mathbb{R} \to \mathbb{R} be a function defined by f(x)=(2+3a)x2+(a+2aβˆ’1)x+b,β€…β€Šaβ‰ 1.f(x) = (2 + 3a)x^2 + \left(\frac{a+2}{a-1}\right)x + b, \; a \ne 1. If f(x+y)=f(x)+f(y)+1βˆ’27xyf(x + y) = f(x) + f(y) + 1 - \frac{2}{7}xy, then the value of 28βˆ‘i=15∣f(i)∣28\sum_{i=1}^{5} |f(i)| is

  1. A

    545545

  2. B

    675675

  3. C

    715715

  4. D

    735735

Show answer

Correct option: B

Q20JEE Main 2025 Jan 28 Shift 1Integral CalculusMedium

If βˆ«βˆ’Ο€2Ο€296x2cos⁑2x(1+ex) dx=Ο€(Ξ±Ο€2+Ξ²)\int_{-\frac{\pi}{2}}^{\frac{\pi}{2}} \frac{96 x^2 \cos^2 x}{(1 + e^x)}\, dx = \pi(\alpha \pi^2 + \beta), Ξ±,β∈Z\alpha, \beta \in \mathbb{Z}, then (Ξ±+Ξ²)2(\alpha + \beta)^2 equals

  1. A

    6464

  2. B

    100100

  3. C

    144144

  4. D

    196196

Show answer

Correct option: B

Q21JEE Main 2025 Jan 28 Shift 1Matrices and DeterminantsHardNumerical

Let M denote the set of all real matrices of order 3Γ—33 \times 3 and let S={βˆ’3,βˆ’2,βˆ’1,1,2}S = \{-3, -2, -1, 1, 2\}. Let S1={A=[aij]∈M:A=ATΒ andΒ aij∈S,βˆ€β€‰i,j}S_1 = \{A = [a_{ij}] \in M : A = A^T \text{ and } a_{ij} \in S, \forall\, i, j\}, S2={A=[aij]∈M:A=βˆ’ATΒ andΒ aij∈S,βˆ€β€‰i,j}S_2 = \{A = [a_{ij}] \in M : A = -A^T \text{ and } a_{ij} \in S, \forall\, i, j\}, S3={A=[aij]∈M:a11+a22+a33=0Β andΒ aij∈S,βˆ€β€‰i,j}S_3 = \{A = [a_{ij}] \in M : a_{11} + a_{22} + a_{33} = 0 \text{ and } a_{ij} \in S, \forall\, i, j\}. If n(S1βˆͺS2βˆͺS3)=125Ξ±n(S_1 \cup S_2 \cup S_3) = 125\alpha, then Ξ±\alpha equals ____.

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Answer: 1613

Q22JEE Main 2025 Jan 28 Shift 1Binomial TheoremMediumNumerical

If Ξ±=1+βˆ‘r=16(βˆ’3)rβˆ’1 12C2rβˆ’1\alpha = 1 + \sum_{r=1}^{6} (-3)^{r-1} \, ^{12}C_{2r-1}, then the distance of the point (12,3)(12, \sqrt{3}) from the line Ξ±xβˆ’3y+1=0\alpha x - \sqrt{3} y + 1 = 0 is ____.

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Answer: 5

Q23JEE Main 2025 Jan 28 Shift 1Conic SectionsMediumNumerical

Let E1:x29+y24=1E_1 : \frac{x^2}{9} + \frac{y^2}{4} = 1 be an ellipse. Ellipses EiE_i's are constructed such that their centres and eccentricities are same as that of E1E_1, and the length of minor axis of EiE_i is the length of major axis of Ei+1E_{i+1} (iβ‰₯1)(i \ge 1). If AiA_i is the area of the ellipse EiE_i, then 5Ο€(βˆ‘i=1∞Ai)\frac{5}{\pi}\left(\sum_{i=1}^{\infty} A_i\right), is equal to ____.

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Answer: 54

Q24JEE Main 2025 Jan 28 Shift 1Vector AlgebraHardNumerical

Let aβƒ—=i^+j^+k^\vec{a} = \hat{i} + \hat{j} + \hat{k}, bβƒ—=2i^+2j^+k^\vec{b} = 2\hat{i} + 2\hat{j} + \hat{k} and dβƒ—=aβƒ—Γ—bβƒ—\vec{d} = \vec{a} \times \vec{b}. If cβƒ—\vec{c} is a vector such that aβƒ—β‹…cβƒ—=∣cβƒ—βˆ£\vec{a} \cdot \vec{c} = |\vec{c}|, ∣cβƒ—βˆ’2aβƒ—βˆ£2=8|\vec{c} - 2\vec{a}|^2 = 8 and the angle between dβƒ—\vec{d} and cβƒ—\vec{c} is Ο€4\frac{\pi}{4}, then ∣10βˆ’3bβƒ—β‹…cβƒ—βˆ£+∣dβƒ—Γ—cβƒ—βˆ£2|10 - 3\vec{b} \cdot \vec{c}| + |\vec{d} \times \vec{c}|^2 is equal to ____.

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Answer: 6

Q25JEE Main 2025 Jan 28 Shift 1Limits, Continuity and DifferentiabilityHardNumerical

Let f(x)={3x,x<0min⁑{1+x+[x],x+2[x]},0≀x≀25,x>2,f(x) = \begin{cases} 3x, & x < 0 \\ \min\{1 + x + [x], x + 2[x]\}, & 0 \le x \le 2 \\ 5, & x > 2, \end{cases} where [.][.] denotes greatest integer function. If Ξ±\alpha and Ξ²\beta are the number of points, where ff is not continuous and is not differentiable, respectively, then Ξ±+Ξ²\alpha + \beta equals ____.

Show answer

Answer: 5

Physics

Q26JEE Main 2025 Jan 28 Shift 1Rotational MotionMedium

The center of mass of a thin rectangular plate (fig - x) with sides of length aa and bb, whose mass per unit area (Οƒ\sigma) varies as Οƒ=Οƒ0xab\sigma = \frac{\sigma_0 x}{ab} (where Οƒ0\sigma_0 is a constant), would be _____

[Figure: fig-x β€” a rectangular plate in the x-y plane with one corner at origin O, side aa along the x-axis and side bb along the y-axis]

  1. A

    (a2,b2)\left(\frac{a}{2}, \frac{b}{2}\right)

  2. B

    (23a,b2)\left(\frac{2}{3}a, \frac{b}{2}\right)

  3. C

    (23a,23b)\left(\frac{2}{3}a, \frac{2}{3}b\right)

  4. D

    (13a,b2)\left(\frac{1}{3}a, \frac{b}{2}\right)

Show answer

Correct option: B

Q27JEE Main 2025 Jan 28 Shift 1Work, Energy and PowerMedium

A bead of mass 'm' slides without friction on the wall of a vertical circular hoop of radius 'R' as shown in figure. The bead moves under the combined action of gravity and a massless spring (k) attached to the bottom of the hoop. The equilibrium length of the spring is 'R'. If the bead is released from top of the hoop with (negligible) zero initial speed, velocity of bead, when the length of spring becomes 'R', would be (spring constant is 'k', g is accleration due to gravity)

[Figure: a vertical circular hoop of diameter 2R resting on the ground, with a spring attached from the bottom of the hoop to the bead at the top]

  1. A

    2gR+kR2m2\sqrt{gR + \frac{kR^2}{m}}

  2. B

    2Rg+4kR2m\sqrt{2Rg + \frac{4kR^2}{m}}

  3. C

    2Rg+kR2m\sqrt{2Rg + \frac{kR^2}{m}}

  4. D

    3Rg+kR2m\sqrt{3Rg + \frac{kR^2}{m}}

Show answer

Correct option: D

Q28JEE Main 2025 Jan 28 Shift 1Work, Energy and PowerMedium

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R

Assertion A: In a central force field, the work done is independent of the path chosen.

Reason R: Every force encountered in mechanics does not have an associated potential energy.

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

  1. A

    Both A and R are true and R is the correct explanation of A

  2. B

    Both A and R are true but R is NOT the correct explanation of A

  3. C

    A is true but R is false

  4. D

    A is false but R is true

Show answer

Correct option: B

Q29JEE Main 2025 Jan 28 Shift 1Properties of Solids and LiquidsMedium

Consider following statements:

A. Surface tension arises due to extra energy of the molecules at the interior as compared to the molecules at the surface, of a liquid.

B. As the temperature of liquid rises, the coefficient of viscosity increases.

C. As the temperature of gas increases, the coefficient of viscosity increases

D. The onset of turbulence is determined by Reynold's number.

E. In a steady flow two stream lines never intersect.

Choose the correct answer from the options given below:

  1. A

    A, D, E Only

  2. B

    C, D, E Only

  3. C

    A, B, C Only

  4. D

    B, C, D Only

Show answer

Correct option: B

Q30JEE Main 2025 Jan 28 Shift 1Experimental SkillsMedium

In the experiment for measurement of viscosity 'Ξ·\eta' of given liquid with a ball having radius R, consider following statements.

A. Graph between terminal velocity V and R will be a parabola.

B. The terminal velocities of different diameter balls are constant for a given liquid.

C. Measurement of terminal velocity is dependent on the temperature.

D. This experiment can be utilized to assess the density of a given liquid.

E. If balls are dropped with some initial speed, the value of Ξ·\eta will change.

  1. A

    A, C and D Only

  2. B

    B, D and E Only

  3. C

    C, D and E Only

  4. D

    A, B and E Only

Show answer

Correct option: A

Q31JEE Main 2025 Jan 28 Shift 1Kinetic Theory of GasesEasy

For a particular ideal gas which of the following graphs represents the variation of mean squared velocity of the gas molecules with temperature?

  1. A

    [Figure: graph of mean squared velocity vs temperature β€” a straight line through the origin increasing linearly]

  2. B

    [Figure: graph of mean squared velocity vs temperature β€” a curve rising to a peak and then decreasing]

  3. C

    [Figure: graph of mean squared velocity vs temperature β€” a concave-down increasing curve (rising with decreasing slope)]

  4. D

    [Figure: graph of mean squared velocity vs temperature β€” a concave-up increasing curve (rising with increasing slope)]

Show answer

Correct option: A

Q32JEE Main 2025 Jan 28 Shift 1ThermodynamicsMedium

A Carnot engine (E) is working between two temperatures 473K and 273K. In a new system two engines - engine E1E_1 works between 473K to 373K and engine E2E_2 works between 373K to 273K. If Ξ·12\eta_{12}, Ξ·1\eta_1 and Ξ·2\eta_2 are the efficiencies of the engines E, E1E_1 and E2E_2, respectively, then

  1. A

    Ξ·12=Ξ·1+Ξ·2\eta_{12} = \eta_1 + \eta_2

  2. B

    Ξ·12β‰₯Ξ·1+Ξ·2\eta_{12} \geq \eta_1 + \eta_2

  3. C

    Ξ·12=Ξ·1Ξ·2\eta_{12} = \eta_1 \eta_2

  4. D

    Ξ·12<Ξ·1+Ξ·2\eta_{12} < \eta_1 + \eta_2

Show answer

Correct option: D

Q33JEE Main 2025 Jan 28 Shift 1WavesEasy

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R

Assertion A: A sound wave has higher speed in solids than gases.

Reason R: Gases have higher value of Bulk modulus than solids.

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

  1. A

    Both A and R are true and R is the correct explanation of A

  2. B

    Both A and R are true but R is NOT the correct explanation of A

  3. C

    A is true but R is false

  4. D

    A is false but R is true

Show answer

Correct option: C

Q34JEE Main 2025 Jan 28 Shift 1Current ElectricityMedium

A wire of resistance R is bent into an equilateral triangle and an identical wire is bent into a square. The ratio of resistance between the two end points of an edge of the triangle to that of the square is

  1. A

    8/98/9

  2. B

    9/89/8

  3. C

    32/2732/27

  4. D

    27/3227/32

Show answer

Correct option: C

Q35JEE Main 2025 Jan 28 Shift 1Magnetic Effects of Current and MagnetismHard

Consider a long thin conducting wire carrying a uniform current I. A particle having mass "M" and charge "q" is released at a distance "aa" from the wire with a speed vov_o along the direction of current in the wire. The particle gets attracted to the wire due to magnetic force. The particle turns round when it is at distance xx from the wire. The value of xx is

[ΞΌ0\mu_0 is the permeability of vacuum]

  1. A

    a eβˆ’4Ο€mvoqΞΌoIa\,e^{-\frac{4\pi m v_o}{q\mu_o I}}

  2. B

    a2\frac{a}{2}

  3. C

    a[1βˆ’mvoqΞΌoI]a\left[1 - \frac{m v_o}{q\mu_o I}\right]

  4. D

    a[1βˆ’mvo2qΞΌoI]a\left[1 - \frac{m v_o}{2q\mu_o I}\right]

Show answer

Correct option: A

Q36JEE Main 2025 Jan 28 Shift 1Current ElectricityMedium

Find the equivalent resistance between two ends of the following circuit

[Figure: circuit between two terminals β€” three resistors each of value r/3r/3: two in series along the lower branch, with a plain wire bridging across the first two, and the third resistor (r/3r/3) in the right portion, with connecting wire loops above and below]

  1. A

    r9\frac{r}{9}

  2. B

    r3\frac{r}{3}

  3. C

    rr

  4. D

    r6\frac{r}{6}

Show answer

Correct option: A

Q37JEE Main 2025 Jan 28 Shift 1ElectrostaticsMedium

A particle of mass 'm' and charge 'q' is fastened to one end 'A' of a massless string having equilibrium length ll, whose other end is fixed at point 'O'. The whole system is placed on a frictionless horizontal plane and is initially at rest. If a uniform electric field is switched on along the direction as shown in figure, then the speed of the particle when it crosses the x-axis is

[Figure: x-y axes with origin at O; a uniform electric field E points along the +x direction; the string OA of length ll makes an angle of 60Β° with the x-axis, with the particle at end A]

  1. A

    2qElm\sqrt{\frac{2qEl}{m}}

  2. B

    qElm\sqrt{\frac{qEl}{m}}

  3. C

    qEl2m\sqrt{\frac{qEl}{2m}}

  4. D

    qEl4m\sqrt{\frac{qEl}{4m}}

Show answer

Correct option: B

Q38JEE Main 2025 Jan 28 Shift 1ElectrostaticsMedium

Two capacitors C1C_1 and C2C_2 are connected in parallel to a battery. The charge-time graph for both the capacitors is shown below. The energies stored in them are U1U_1 and U2U_2 respectively. Which of the given statements is true?

[Figure: graph of charge q vs time t showing two rising curves β€” curve C1C_1 rises faster initially and saturates at a lower charge; curve C2C_2 rises slower but saturates at a higher charge]

  1. A

    C1>C2C_1 > C_2, U1>U2U_1 > U_2

  2. B

    C1>C2C_1 > C_2, U1<U2U_1 < U_2

  3. C

    C2>C1C_2 > C_1, U2>U1U_2 > U_1

  4. D

    C2>C1C_2 > C_1, U2<U1U_2 < U_1

Show answer

Correct option: C

Q39JEE Main 2025 Jan 28 Shift 1ElectrostaticsHard

Three infinitely long wires with linear charge density Ξ»\lambda are placed along the x-axis, y-axis and z-axis respectively. Which of the following denotes an equipotential surface?

  1. A

    xyz=constantxyz = \text{constant}

  2. B

    (x+y)(y+z)(z+x)=constant(x + y)(y + z)(z + x) = \text{constant}

  3. C

    (x2+y2)(y2+z2)(z2+x2)=constant(x^2 + y^2)(y^2 + z^2)(z^2 + x^2) = \text{constant}

  4. D

    xy+yz+zx=constantxy + yz + zx = \text{constant}

Show answer

Correct option: C

Q40JEE Main 2025 Jan 28 Shift 1Electromagnetic WavesMedium

Due to presence of an em-wave whose electric component is given by E=100sin⁑(Ο‰tβˆ’kx)Β NCβˆ’1E = 100 \sin(\omega t - kx)\ \mathrm{NC^{-1}}, a cylinder of length 200 cm holds certain amount of em-energy inside it. If another cylinder of same length but half diameter than previous one holds same amount of em-energy, the magnitude of the electric field of the corresponding em-wave should be modified as

  1. A

    50sin⁑(Ο‰tβˆ’kx)Β NCβˆ’150 \sin(\omega t - kx)\ \mathrm{NC^{-1}}

  2. B

    200sin⁑(Ο‰tβˆ’kx)Β NCβˆ’1200 \sin(\omega t - kx)\ \mathrm{NC^{-1}}

  3. C

    25sin⁑(Ο‰tβˆ’kx)Β NCβˆ’125 \sin(\omega t - kx)\ \mathrm{NC^{-1}}

  4. D

    400sin⁑(Ο‰tβˆ’kx)Β NCβˆ’1400 \sin(\omega t - kx)\ \mathrm{NC^{-1}}

Show answer

Correct option: B

Q41JEE Main 2025 Jan 28 Shift 1Ray OpticsMedium

A hemispherical vessel is completely filled with a liquid of refractive index ΞΌ\mu. A small coin is kept at the lowest point (O) of the vessel as shown in figure. The minimum value of the refractive index of the liquid so that a person can see the coin from point E (at the level of the vessel) is _____.

[Figure: a hemispherical vessel filled with liquid, rim points A and B at the top with centre C; coin at the lowest point O; point E lies outside the vessel at the level of the rim, to the right of B]

  1. A

    32\frac{3}{2}

  2. B

    2\sqrt{2}

  3. C

    32\frac{\sqrt{3}}{2}

  4. D

    3\sqrt{3}

Show answer

Correct option: B

Q42JEE Main 2025 Jan 28 Shift 1Ray OpticsMedium

A thin prism P1P_1 with angle 4Β° made of glass having refractive index 1.54, is combined with another thin prism P2P_2 made of glass having refractive index 1.72 to get dispersion without deviation. The angle of the prism P2P_2 in degrees is

  1. A

    33

  2. B

    16/316/3

  3. C

    44

  4. D

    1.51.5

Show answer

Correct option: A

Q43JEE Main 2025 Jan 28 Shift 1Dual Nature of Matter and RadiationMedium

A proton of mass 'mpm_p' has same energy as that of a photon of wavelength 'Ξ»\lambda'. If the proton is moving at non-relativistic speed, then ratio of its de Broglie wavelength to the wavelength of photon is.

  1. A

    1cEmp\frac{1}{c}\sqrt{\frac{E}{m_p}}

  2. B

    1cE2mp\frac{1}{c}\sqrt{\frac{E}{2m_p}}

  3. C

    12cEmp\frac{1}{2c}\sqrt{\frac{E}{m_p}}

  4. D

    1c2Emp\frac{1}{c}\sqrt{\frac{2E}{m_p}}

Show answer

Correct option: B

Q44JEE Main 2025 Jan 28 Shift 1Atoms and NucleiEasy

Choose the correct nuclear process from the below options

[p: proton, n: neutron, eβˆ’e^-: electron, e+e^+: positron, Ξ½\nu: neutrino, Ξ½Λ‰\bar{\nu}: antineutrino]

  1. A

    nβ†’p+eβˆ’+Ξ½n \rightarrow p + e^- + \nu

  2. B

    n→p+e++νˉn \rightarrow p + e^+ + \bar{\nu}

  3. C

    nβ†’p+eβˆ’+Ξ½Λ‰n \rightarrow p + e^- + \bar{\nu}

  4. D

    n→p+e++νn \rightarrow p + e^+ + \nu

Show answer

Correct option: C

Q45JEE Main 2025 Jan 28 Shift 1Electronic DevicesMedium

Which of the following circuits has the same outpur as that of the given circuit?

[Figure: logic circuit β€” inputs A and B; B is passed through a NOT gate; one AND gate receives A and NOT B, another AND gate receives A and B; the outputs of the two AND gates feed a NOR gate whose output is Y]

  1. A

    [Figure: a NAND gate with both inputs connected to B, output Y]

  2. B

    [Figure: a NAND gate with both inputs connected to A, output Y]

  3. C

    [Figure: an AND gate with inputs A and B, output Y]

  4. D

    [Figure: an AND gate with inputs A and B followed by a NOT gate, output Y]

Show answer

Correct option: B

Q46JEE Main 2025 Jan 28 Shift 1Units and MeasurementsMediumNumerical

In a measurement, it is asked to find modulus of elasticity per unit torque applied on the system. The measured quantity has dimension of [Ma Lb Tc][\mathrm{M^a\, L^b\, T^c}]. If b = 3, the value of c is _____

Show answer

Answer: 0

Q47JEE Main 2025 Jan 28 Shift 1Experimental SkillsMediumNumerical

A tiny metallic rectangular sheet has length and breadth of 5 mm and 2.5 mm, respectively. Using a specially designed screw gauge which has pitch of 0.75 mm and 15 divisions in the circular scale, you are asked to find the area of the sheet. In this measurement, the maximum fractional error will be x100\frac{x}{100} where xx is ________ .

Show answer

Answer: 3

Q48JEE Main 2025 Jan 28 Shift 1Rotational MotionMediumNumerical

Two iron solid discs of negligible thickness have radii R1R_1 and R2R_2 and moment of intertia I1I_1 and I2I_2, respectively. For R2=2R1R_2 = 2R_1, the ratio of I1I_1 and I2I_2 would be 1/x1/x, where xx = _____.

Show answer

Answer: 16

Q49JEE Main 2025 Jan 28 Shift 1Rotational MotionMediumNumerical

The moment of inertia of a solid disc rotating along its diameter is 2.5 times higher than the moment of inertia of a ring rotating in similar way. The moment of inertia of a solid sphere which has same radius as the disc and rotating in similar way, is n times higher than the moment of inertia of the given ring. Here, n = _____. Consider all the bodies have equal masses.

Show answer

Answer: 4

Q50JEE Main 2025 Jan 28 Shift 1Wave OpticsEasyNumerical

A double slit interference experiment performed with a light of wavelength 600 nm forms an interference fringe pattern on a screen with 10th bright fringe having its centre at a distance of 10 mm from the central maximum. Distance of the centre of the same 10th bright fringe from the central maximum when the source of light is replaced by another source of wavelength 660 nm would be _____ mm.

Show answer

Answer: 11

Chemistry

Q51JEE Main 2025 Jan 28 Shift 1Some Basic Concepts in ChemistryMedium

[Stem unrecoverable: the PDF pages carrying this question's stem are corrupted in both the English and Hindi copies. The options indicate a five-statement (A-E) multiple-select question. Option texts below are recovered from the Hindi copy.]

  1. A

    D and E Only

  2. B

    C and D Only

  3. C

    B and C Only

  4. D

    A and B Only

Show answer

Correct option: A

Q52JEE Main 2025 Jan 28 Shift 1Chemical Bonding and Molecular StructureEasy

The molecules having square pyramidal geometry are

  1. A

    BrF5\mathrm{BrF_5} & PCl5\mathrm{PCl_5}

  2. B

    SbF5\mathrm{SbF_5} & XeOF4\mathrm{XeOF_4}

  3. C

    BrF5\mathrm{BrF_5} & XeOF4\mathrm{XeOF_4}

  4. D

    SbF5\mathrm{SbF_5} & PCl5\mathrm{PCl_5}

Show answer

Correct option: C

Q53JEE Main 2025 Jan 28 Shift 1SolutionsEasy

What is the freezing point depression constant of a solvent, 50 g of which contain 1 g non volatile solute (molar mass 256 g molβˆ’1^{-1}) and the decrease in freezing point is 0.40 K ?

  1. A

    1.86Β KΒ kgΒ molβˆ’11.86\ \mathrm{K\ kg\ mol^{-1}}

  2. B

    3.72Β KΒ kgΒ molβˆ’13.72\ \mathrm{K\ kg\ mol^{-1}}

  3. C

    5.12Β KΒ kgΒ molβˆ’15.12\ \mathrm{K\ kg\ mol^{-1}}

  4. D

    4.43Β KΒ kgΒ molβˆ’14.43\ \mathrm{K\ kg\ mol^{-1}}

Show answer

Correct option: C

Q54JEE Main 2025 Jan 28 Shift 1EquilibriumMedium

Ice and water are placed in a closed container at a pressure of 1 atm and temperature 273.15 K. If pressure of the system is increased 2 times, keeping temperature constant, then identify correct observation from following

  1. A

    Liquid phase disappears completely.

  2. B

    The amount of ice decreases.

  3. C

    The solid phase (ice) disappears completely.

  4. D

    Volume of system increases .

Show answer

Correct option: C

Q55JEE Main 2025 Jan 28 Shift 1EquilibriumMedium

A weak acid HA has degree of dissociation x. Which of the following options correctly explains (pHβˆ’pKa\mathrm{pH} - \mathrm{p}K_a)?

  1. A

    log⁑(1+2x)\log(1 + 2x)

  2. B

    log⁑(1βˆ’xx)\log\left(\dfrac{1-x}{x}\right)

  3. C

    0

  4. D

    log⁑(x1βˆ’x)\log\left(\dfrac{x}{1-x}\right)

Show answer

Correct option: D

Q56JEE Main 2025 Jan 28 Shift 1Redox Reactions and ElectrochemistryEasy

Match the LIST-I with LIST-II

LIST-I (Redox Reaction) LIST-II (Type of Redox Reaction)
A. CH4(g)+2O2(g)β†’Ξ”CO2(g)+2H2O(l)\mathrm{CH_{4(g)} + 2O_{2(g)} \xrightarrow{\Delta} CO_{2(g)} + 2H_2O_{(l)}} I. Disproportionation reaction
B. 2NaH(s)β†’Ξ”2Na(s)+H2(g)\mathrm{2NaH_{(s)} \xrightarrow{\Delta} 2Na_{(s)} + H_{2(g)}} II. Combination reaction
C. V2O5(s)+5Ca(s)β†’Ξ”2V(s)+5CaO(s)\mathrm{V_2O_{5(s)} + 5Ca_{(s)} \xrightarrow{\Delta} 2V_{(s)} + 5CaO_{(s)}} III. Decomposition reaction
D. 2H2O2(aq)β†’Ξ”2H2O(l)+O2(g)\mathrm{2H_2O_{2(aq)} \xrightarrow{\Delta} 2H_2O_{(l)} + O_{2(g)}} IV. Displacement reaction

Choose the correct answer from the options given below:

  1. A

    A-III, B-IV, C-I, D-II

  2. B

    A-IV, B-I, C-II, D-III

  3. C

    A-II, B-III, C-IV, D-I

  4. D

    A-II, B-III, C-I, D-IV

Show answer

Correct option: C

Q57JEE Main 2025 Jan 28 Shift 1Chemical KineticsMedium

For a given reaction R→P\mathrm{R \to P}, t1/2t_{1/2} is related to [A]0[\mathrm{A}]_0 as given in table.

[A]0/molΒ Lβˆ’1[\mathrm{A}]_0/\mathrm{mol\ L^{-1}} t1/2/mint_{1/2}/\mathrm{min}
0.100 200
0.025 100

Given: log⁑2=0.30\log 2 = 0.30

Which of the following is true?

A. The order of the reaction is 12\frac{1}{2}.

B. If [A]0[\mathrm{A}]_0 is 1M, then t1/2t_{1/2} is 20010200\sqrt{10} min

C. The order of the reaction changes to 1 if the concentration of reactant changes from 0.100 M to 0.500 M.

D. t1/2t_{1/2} is 800 min for [A]0=1.6[\mathrm{A}]_0 = 1.6 M

Choose the correct answer from the options given below:

  1. A

    A and B Only

  2. B

    A and C Only

  3. C

    A, B and D Only

  4. D

    C and D Only

Show answer

Correct option: C

Q58JEE Main 2025 Jan 28 Shift 1Classification of Elements and PeriodicityMedium

The incorrect decreasing order of atomic radii is

  1. A

    Al>B>N>F\mathrm{Al > B > N > F}

  2. B

    Mg>Al>C>O\mathrm{Mg > Al > C > O}

  3. C

    Be>Mg>Al>Si\mathrm{Be > Mg > Al > Si}

  4. D

    Si>P>Cl>F\mathrm{Si > P > Cl > F}

Show answer

Correct option: C

Q59JEE Main 2025 Jan 28 Shift 1p-Block ElementsMedium

Consider the following elements In, Tl, Al, Pb, Sn and Ge.

The most stable oxidation states of elements with highest and lowest first ionisation enthalpies, respectively, are

  1. A

    +1 and +4

  2. B

    +2 and +3

  3. C

    +4 and +1

  4. D

    +4 and +3

Show answer

Correct option: D

Q60JEE Main 2025 Jan 28 Shift 1d- and f-Block ElementsMedium

Which of the following oxidation reactions are carried out by both K2Cr2O7\mathrm{K_2Cr_2O_7} and KMnO4\mathrm{KMnO_4} in acidic medium?

A. Iβˆ’β†’I2\mathrm{I^- \to I_2}

B. S2βˆ’β†’S\mathrm{S^{2-} \to S}

C. Fe2+β†’Fe3+\mathrm{Fe^{2+} \to Fe^{3+}}

D. Iβˆ’β†’IO3βˆ’\mathrm{I^- \to IO_3^-}

E. S2O32βˆ’β†’SO42βˆ’\mathrm{S_2O_3^{2-} \to SO_4^{2-}}

Choose the correct answer from the options given below:

  1. A

    A, B and C Only

  2. B

    B, C and D Only

  3. C

    C, D and E Only

  4. D

    A, D and E Only

Show answer

Correct option: A

Q61JEE Main 2025 Jan 28 Shift 1d- and f-Block ElementsMedium

Consider 'n' is the number of lone pair of electrons present in the equatorial position of the most stable structure of ClF3\mathrm{ClF_3}. The ions from the following with 'n' number of unpaired electrons are

A. V3+\mathrm{V^{3+}}

B. Ti3+\mathrm{Ti^{3+}}

C. Cu2+\mathrm{Cu^{2+}}

D. Ni2+\mathrm{Ni^{2+}}

E. Ti2+\mathrm{Ti^{2+}}

Choose the correct answer from the options given below:

  1. A

    B and C Only

  2. B

    A and C Only

  3. C

    A, D and E Only

  4. D

    B and D Only

Show answer

Correct option: C

Q62JEE Main 2025 Jan 28 Shift 1d- and f-Block ElementsMedium

[Stem unrecoverable: the PDF page carrying this question's stem is corrupted in both the English and Hindi copies. The visible options are transition-metal ions; the first two options are images that are also unrecoverable.]

  1. A

    [Option unrecoverable: corrupted image in PDF]

  2. B

    [Option unrecoverable: corrupted image in PDF]

  3. C

    Ti3+\mathrm{Ti^{3+}}

  4. D

    Mn2+\mathrm{Mn^{2+}}

Show answer

Correct option: A

Q63JEE Main 2025 Jan 28 Shift 1Organic Compounds Containing HalogensMedium

Given below are two statements:

Statement I: [Structure: Et2Nβˆ’CH2CH2βˆ’Cl\mathrm{Et_2N{-}CH_2CH_2{-}Cl}] will undergo alkaline hydrolysis at a faster rate than [Structure: Et2CHβˆ’CH2CH2βˆ’Cl\mathrm{Et_2CH{-}CH_2CH_2{-}Cl}]

Statement II: In [Structure: Et2Nβˆ’CH2CH2βˆ’Cl\mathrm{Et_2N{-}CH_2CH_2{-}Cl}] , intramolecular substitution takes place first by involving lone pair of electrons on nitrogen.

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

  1. A

    Both Statement I and Statement II are correct

  2. B

    Both Statement I and Statement II are incorrect

  3. C

    Statement I is correct but Statement II is incorrect

  4. D

    Statement I is incorrect but Statement II is correct

Show answer

Correct option: A

Q64JEE Main 2025 Jan 28 Shift 1Some Basic Principles of Organic ChemistryEasy

The correct order of stability of following carbocations is :

[Figure: A = Ph3CβŠ•\mathrm{Ph_3C^{\oplus}} (triphenylmethyl cation); B = Ph2CβŠ•H\mathrm{Ph_2\overset{\oplus}{C}H} (diphenylmethyl cation); C = tropylium (cycloheptatrienyl) cation; D = H3Cβˆ’CH2βˆ’CβŠ•Hβˆ’CH3\mathrm{H_3C{-}CH_2{-}\overset{\oplus}{C}H{-}CH_3} (butan-2-ylium cation)]

  1. A

    C > A > B > D

  2. B

    A > B > C > D

  3. C

    C > B > A > D

  4. D

    B > C > A > D

Show answer

Correct option: A

Q65JEE Main 2025 Jan 28 Shift 1Organic Compounds Containing OxygenHard

A molecule ("P") on treatment with acid undergoes rearrangement and gives ("Q"). ("Q") on ozonolysis followed by reflux under alkaline condition gives ("R"). The structure of ("R") is given below.

[Figure: "R" = 1-(2-methylcyclopent-1-en-1-yl)ethan-1-one β€” a cyclopentene ring bearing a COCH3\mathrm{COCH_3} group at C1 and a CH3\mathrm{CH_3} group at C2]

The structure of ("P") is

  1. A

    [Figure: 1-isopropylcyclopentan-1-ol β€” cyclopentane ring with OH and CH(CH3)2\mathrm{CH(CH_3)_2} on the same carbon]

  2. B

    [Figure: 1-isopropylcyclobutan-1-ol β€” cyclobutane ring with OH and CH(CH3)2\mathrm{CH(CH_3)_2} (Me, Me) on the same carbon]

  3. C

    [Figure: 1,2-dimethylcyclohexene β€” cyclohexene ring with CH3\mathrm{CH_3} groups on both double-bond carbons]

  4. D

    [Figure: prop-1-en-2-ylcyclopentane β€” cyclopentane ring bearing an isopropenyl group C(CH3)=CH2\mathrm{C(CH_3){=}CH_2}]

Show answer

Correct option: A, D (dropped β€” all options accepted)

Q66JEE Main 2025 Jan 28 Shift 1Organic Compounds Containing HalogensEasy

The products A and B in the following reactions, respectively are

A←Agβˆ’NO2CH3βˆ’CH2βˆ’CH2βˆ’Brβ†’AgCNB\mathrm{A} \xleftarrow{\mathrm{Ag{-}NO_2}} \mathrm{CH_3{-}CH_2{-}CH_2{-}Br} \xrightarrow{\mathrm{AgCN}} \mathrm{B}

  1. A

    CH3βˆ’CH2βˆ’CH2βˆ’NO2\mathrm{CH_3-CH_2-CH_2-NO_2} , CH3βˆ’CH2βˆ’CH2βˆ’CN\mathrm{CH_3-CH_2-CH_2-CN}

  2. B

    CH3βˆ’CH2βˆ’CH2βˆ’ONO\mathrm{CH_3-CH_2-CH_2-ONO} , CH3βˆ’CH2βˆ’CH2βˆ’CN\mathrm{CH_3-CH_2-CH_2-CN}

  3. C

    CH3βˆ’CH2βˆ’CH2βˆ’ONO\mathrm{CH_3-CH_2-CH_2-ONO} , CH3βˆ’CH2βˆ’CH2βˆ’NC\mathrm{CH_3-CH_2-CH_2-NC}

  4. D

    CH3βˆ’CH2βˆ’CH2βˆ’NO2\mathrm{CH_3-CH_2-CH_2-NO_2} , CH3βˆ’CH2βˆ’CH2βˆ’NC\mathrm{CH_3-CH_2-CH_2-NC}

Show answer

Correct option: D

Q67JEE Main 2025 Jan 28 Shift 1Organic Compounds Containing OxygenMedium

Both acetaldehyde and acetone (individually) undergo which of the following reactions?

A. Iodoform Reaction

B. Cannizaro Reaction

C. Aldol Condensation

D. Tollen's Test

E. Clemmensen Reduction

Choose the correct answer from the options given below:

  1. A

    A, C and E Only

  2. B

    C and E Only

  3. C

    B, C and D Only

  4. D

    A, B and D Only

Show answer

Correct option: A

Q68JEE Main 2025 Jan 28 Shift 1Organic Compounds Containing NitrogenMedium

[Stem unrecoverable: the PDF pages carrying this question's stem are corrupted in both the English and Hindi copies. The options indicate a five-statement (A-E) multiple-select question. Option texts below are recovered from the Hindi copy.]

  1. A

    A and C Only

  2. B

    A and B Only

  3. C

    A, B and E Only

  4. D

    A, C and D Only

Show answer

Correct option: D

Q69JEE Main 2025 Jan 28 Shift 1BiomoleculesMedium

Given below are two statements:

Statement I : D-glucose pentaacetate reacts with 2, 4 - dinitrophenylhydrazine

Statement II : Starch, on heating with concentrated sulfuric acid at 100Β°C and 2 - 3 atmosphere pressure produces glucose.

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

  1. A

    Both Statement I and Statement II are true

  2. B

    Both Statement I and Statement II are false

  3. C

    Statement I is true but Statement II is false

  4. D

    Statement I is false but Statement II is true

Show answer

Correct option: D

Q70JEE Main 2025 Jan 28 Shift 1Principles Related to Practical ChemistryMedium

Given below are two statements:

Statement I: In the oxalic acid vs KMnO4\mathrm{KMnO_4} (in the presence of dil H2SO4\mathrm{H_2SO_4}) titration the solution needs to be heated initially to 60Β°C, but no heating is required in Ferrous ammonium sulphate (FAS) vs KMnO4\mathrm{KMnO_4} titration (in the presence of dil H2SO4\mathrm{H_2SO_4})

Statement II: In oxalic acid vs KMnO4\mathrm{KMnO_4} titration, the initial formation of MnSO4\mathrm{MnSO_4} takes place at high temperature, which then acts as catalyst for further reaction. In the case of FAS vs KMnO4\mathrm{KMnO_4}, heating oxidizes Fe2+\mathrm{Fe^{2+}} into Fe3+\mathrm{Fe^{3+}} by oxygen of air and error may be introduced in the experiment.

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

  1. A

    Both Statement I and Statement II are true

  2. B

    Both Statement I and Statement II are false

  3. C

    Statement I is true but Statement II is false

  4. D

    Statement I is false but Statement II is true

Show answer

Correct option: A

Q71JEE Main 2025 Jan 28 Shift 1Some Basic Concepts in ChemistryEasyNumerical

The molarity of a 70% (mass/mass) aqueous solution of a monobasic acid (X) is _____ Γ—Β 10βˆ’1\times\ 10^{-1} M(Nearest integer)

[Given: Density of aqueous solution of (X) is 1.25Β gΒ mLβˆ’11.25\ \mathrm{g\ mL^{-1}}

Molar mass of the acid is 70Β gΒ molβˆ’170\ \mathrm{g\ mol^{-1}} ]

Show answer

Answer: 125

Q72JEE Main 2025 Jan 28 Shift 1Chemical ThermodynamicsMediumNumerical

The formation enthalpies, Ξ”HfβŠ–\Delta H_f^{\ominus} for H(g)\mathrm{H_{(g)}} and O(g)\mathrm{O_{(g)}} are 220.0 and 250.0 kJΒ molβˆ’1\mathrm{kJ\ mol^{-1}}, respectively, at 298.15 K, and Ξ”HfβŠ–\Delta H_f^{\ominus} for H2O(g)\mathrm{H_2O_{(g)}} is βˆ’242.0Β kJΒ molβˆ’1-242.0\ \mathrm{kJ\ mol^{-1}} at the same temperature. The average bond enthalpy of the Oβˆ’H\mathrm{O{-}H} bond in water at 298.15 K is _______ kJΒ molβˆ’1\mathrm{kJ\ mol^{-1}} (nearest integer).

Show answer

Answer: 466

Q73JEE Main 2025 Jan 28 Shift 1Redox Reactions and ElectrochemistryMediumNumerical

Given below is the plot of the molar conductivity vs concentration\sqrt{\text{concentration}} for KCl in aqueous solution.

[Figure: graph of molar conductivity Ξ›mΒ (SΒ cm2Β molβˆ’1)\Lambda_m\ (\mathrm{S\ cm^2\ mol^{-1}}) vs CΒ (mol/L)1/2\sqrt{C}\ (\mathrm{mol/L})^{1/2} β€” a straight line with negative slope passing through Ξ›m=150\Lambda_m = 150 at C=0.1\sqrt{C} = 0.1 and Ξ›m=100\Lambda_m = 100 at C=0.15\sqrt{C} = 0.15]

If, for the higher concentration of KCl solution, the resistance of the conductivity cell is 100 Ξ©\Omega, then the resistance of the same cell with the dilute solution is 'x' Ξ©\Omega.

The value of x is ______ (Nearest integer)

Show answer

Answer: 150

Q74JEE Main 2025 Jan 28 Shift 1Purification and Characterisation of Organic CompoundsMediumNumerical

Quantitative analysis of an organic compound (X) shows following % composition.

C : 14.5 %  Cl : 64.46%

H : 1.8 %

(Empirical formula mass of the compound (X) is ____ Γ—10βˆ’1\times 10^{-1}

(Given molar mass in gΒ molβˆ’1\mathrm{g\ mol^{-1}} of C : 12, H : 1, O : 16, Cl : 35.5)

Show answer

Answer: 1655

Q75JEE Main 2025 Jan 28 Shift 1Organic Compounds Containing NitrogenMediumNumerical

Consider the following sequence of reactions:

[Figure: benzene ring with Cl substituent (Chlorobenzene)]

Chlorobenzene→ii) CO2,H3O+iii) NH3, Δi) Mg, dry etherA→Br2, NaOHB\text{Chlorobenzene} \xrightarrow[\substack{\text{ii) } \mathrm{CO_2, H_3O^+} \\ \text{iii) } \mathrm{NH_3},\ \Delta}]{\text{i) Mg, dry ether}} \mathrm{A} \xrightarrow{\mathrm{Br_2,\ NaOH}} \mathrm{B}

11.25 mg of chlorobenzene will produce ---- x10βˆ’1\mathrm{x}10^{-1} mg of product B.

(Consider the reactions result in complete conversion.)

[Given molar mass of C, H, O, N and Cl as 12, 1, 16, 14 and 35.5 gΒ molβˆ’1\mathrm{g\ mol^{-1}} respectively]

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Answer: 93