JEE Main 2024 — 29 Jan Shift 2 (Previous Year Paper)
JEE Main · 2024 · with answers and explanations
- questions
- 90
- Total marks
- 300
- Duration
- 180 minutes
- Negative marking
- −1
Subjects: Mathematics · Physics · Chemistry
Question 1
Mathematics · 4 marks · −1If is the smallest equivalence relation on the set such that , then the number of elements in is ______.
- A.10
- B.8
- C.12
- D.15
Correct answer: A
Explanation: Classes and : pairs.
Question 2
Mathematics · 4 marks · −1If the mean and variance of five observations are and respectively and the mean of the first four observations is , then the variance of the first four observations in equal to:
- A.
- B.
- C.
- D.
Correct answer: B
Explanation: , ; the fifth value is 10, so the first four have , ; variance .
Question 3
Mathematics · 4 marks · −1Let , . Then at , the value of is equal to:
- A.746
- B.742
- C.732
- D.736
Correct answer: D
Explanation: , at ; .
Question 4
Mathematics · 4 marks · −1The function , .
- A.decreases in
- B.increases in
- C.decreases in and increases in
- D.decreases in and increases in
Correct answer: A
Explanation: .
Question 5
Mathematics · 4 marks · −1If , where is the integration constant, then AB is equal to:
- A.
- B.
- C.
- D.
Correct answer: C
Explanation: Split the integrand: gives and gives ; .
Question 6
Mathematics · 4 marks · −1The function , has:
- A.exactly one point of local minima and no point of local maxima
- B.exactly one point of local maxima and no point of local minima
- C.exactly two points of local maxima and exactly one point of local minima
- D.exactly one point of local maxima and exactly one point of local minima
Correct answer: D
Explanation: : maximum at , minimum at (cusp).
Question 7
Mathematics · 4 marks · −1If , , are in an A.P. and , , are also in an A.P., then is equal to:
- A.25 : 10 : 4
- B.6 : 3 : 2
- C.16 : 4 : 1
- D.9 : 6 : 4
Correct answer: D
Explanation: and , so ; .
Question 8
Mathematics · 4 marks · −1Let and . The sum of the prime factors of is equal to:
- A.26
- B.27
- C.66
- D.23
Correct answer: A
Explanation: .
Question 9
Mathematics · 4 marks · −1The distance of the point (2, 3) from the line , measured parallel to the line , is equal to:
- A.
- B.
- C.
- D.
Correct answer: B
Explanation: Point on the line gives .
Question 10
Mathematics · 4 marks · −1If each term of a geometric progression with and , is the arithmetic mean of the next two terms and , then is equal to:
- A.
- B.
- C.
- D.
Correct answer: A
Explanation: ; .
Question 11
Mathematics · 4 marks · −1An integer is chosen at random from the integers 1, 2, 3, ...., 50. The probability that the chosen integer is a multiple of atleast one of 4, 6 and 7 is:
- A.
- B.
- C.
- D.
Correct answer: A
Explanation: .
Question 12
Mathematics · 4 marks · −1Number of ways of arranging 8 identical books into 4 identical shelves where any number of shelves may remain empty is equal to:
- A.16
- B.12
- C.18
- D.15
Correct answer: D
Explanation: Partitions of 8 into at most 4 parts: 15.
Question 13
Mathematics · 4 marks · −1Let , and be the vertices of . Then, the angle is:
- A.
- B.
- C.
- D.
Correct answer: A
Explanation: , ; .
Question 14
Mathematics · 4 marks · −1Let a unit vector make angles and with the vectors , and respectively. If , then is equal to:
- A.
- B.9
- C.
- D.7
Correct answer: C
Explanation: , , give ; .
Question 15
Mathematics · 4 marks · −1Let , and , where is the origin. If is the parallelogram with adjacent sides OA and OC, then is equal to ______.
- A.10
- B.7
- C.6
- D.8
Correct answer: D
Explanation: Area .
Question 16
Mathematics · 4 marks · −1The sum of the solutions of the equation is:
- A.1
- B.0
- C.−1
- D.3
Correct answer: C
Explanation: , so LHS ; has the single real root .
Question 17
Mathematics · 4 marks · −1Let ( are co-prime natural numbers) be a solution of the equation and let be the roots of the equation . Then the point lies on the line.
- A.
- B.
- C.
- D.
Correct answer: A
Explanation: ; : .
Question 18
Mathematics · 4 marks · −1Let be the point of intersection of the lines , and be the point of intersection of the lines , . The distance of the point from the line is:
- A.
- B.6
- C.8
- D.
Correct answer: B
Explanation: , ; ; distance .
Question 19
Mathematics · 4 marks · −1Let and respectively be the modulus and amplitude of the complex number , then is equal to:
- A.
- B.
- C.
- D.
Correct answer: C
Explanation: .
Question 20
Mathematics · 4 marks · −1If is the solution of the differential equation and , then is equal to:
- A.4
- B.12
- C.9
- D.3
Correct answer: D
Explanation: With : ; gives .
Question 21
Mathematics · 4 marks · −1Let the area of the region be . Then is equal to ______.
Correct answer: 164
Explanation: ; .
Question 22
Mathematics · 4 marks · −1Remainder when is divided by 9 is equal to ______.
Correct answer: 1
Explanation: .
Question 23
Mathematics · 4 marks · −1Let be the roots of the equation such that . Let be integers not divisible by 3 and be a natural number such that , . Then is equal to ______.
Correct answer: 49
Question 24
Mathematics · 4 marks · −1Let the set . Then is equal to ______.
Correct answer: 46
Explanation: Only works (), so the sum is 46.
Question 25
Mathematics · 4 marks · −1If , where and are rational numbers, then is equal to ______.
Correct answer: 6
Question 26
Mathematics · 4 marks · −1Let be differentiable in and . Then the value of , such that , is equal to ______.
Correct answer: 2
Question 27
Mathematics · 4 marks · −1Let for any three distinct consecutive terms of an A.P. the lines be concurrent at the point and be a point such that the system of equations and , has infinitely many solutions. The is equal to ______.
Correct answer: 113
Explanation: so every line passes through . The system is dependent when , and gives ; .
Question 28
Mathematics · 4 marks · −1Let the slope of the line be for some . Then is equal to ______.
Correct answer: 12
Question 29
Mathematics · 4 marks · −1Let be the origin, and and be the points on the lines and respectively such that is the shortest distance between the given lines. Then is equal to ______.
Correct answer: 9
Question 30
Mathematics · 4 marks · −1Let be a point on the parabola . If also lies on the chord of the parabola whose mid-point is , then is equal to ______.
Correct answer: 192
Question 31
Physics · 4 marks · −1N moles of a polyatomic gas () must be mixed with two moles of a monoatomic gas so that the mixture behaves as a diatomic gas. The value of N is:
- A.4
- B.2
- C.3
- D.6
Correct answer: A
Explanation: .
Question 32
Physics · 4 marks · −1The truth table for this given circuit is:

- A.A B Y: 0 0 0; 0 1 0; 1 0 0; 1 1 1
- B.A B Y: 0 0 1; 0 1 0; 1 0 1; 1 1 0
- C.A B Y: 0 0 1; 0 1 1; 1 0 1; 1 1 0
- D.A B Y: 0 0 0; 0 1 1; 1 0 0; 1 1 1
Correct answer: D
Explanation: .
Question 33
Physics · 4 marks · −1Two particles X and Y having equal charges are being accelerated through the same potential difference. Thereafter they enter normally in a region of uniform magnetic field and describes circular paths of radii and respectively. The mass ratio of X and Y is:
- A.
- B.
- C.
- D.
Correct answer: B
Explanation: .
Question 34
Physics · 4 marks · −1In the given circuit, the current in resistance is:

- A.1.5 A
- B.2.5 A
- C.2 A
- D.1 A
Correct answer: D
Explanation: Total , A, split equally: 1 A.
Question 35
Physics · 4 marks · −1In Young's double slit experiment, light from two identical sources are superimposing on a screen. The path difference between the two lights reaching at a point on the screen is . The ratio of intensity of fringe at this point with respect to the maximum intensity of the fringe is:
- A.
- B.
- C.
- D.
Correct answer: A
Explanation: ; .
Question 36
Physics · 4 marks · −1An electric field is given by N/C. The electric flux through a surface area m² lying in YZ-plane (in SI unit) is:
- A.180
- B.150
- C.90
- D.60
Correct answer: A
Question 37
Physics · 4 marks · −1A plane electromagnetic wave of frequency 35 MHz travels in free space along the X-direction. At a particular point (in space and time) V/m. The value of magnetic field at this point is:
- A. T
- B. T
- C. T
- D. T
Correct answer: D
Explanation: and .
Question 38
Physics · 4 marks · −1A bob of mass 'm' is suspended by a light string of length 'L'. It is imparted a minimum horizontal velocity at the lowest point A such that it just completes half circle reaching the top most position B. The ratio of kinetic energies is:

- A.5 : 1
- B.3 : 2
- C.1 : 5
- D.2 : 5
Correct answer: A
Explanation: , .
Question 39
Physics · 4 marks · −1A wire of length L and radius r is clamped at one end. If its other end is pulled by a force F, its length increases by l. If the radius of the wire and the applied force both are reduced to half of their original values keeping original length constant, the increase in length will become:
- A.2 times
- B. times
- C.4 times
- D.3 times
Correct answer: A
Explanation: : .
Question 40
Physics · 4 marks · −1If the distance between object and its two times magnified virtual image produced by a curved mirror is 15 cm. the focal length of the mirror must be:
- A.−12 cm
- B.15 cm
- C.10/3 cm
- D.−10 cm
Correct answer: D
Explanation: , , ; cm.
Question 41
Physics · 4 marks · −1The bob of a pendulum was released from a horizontal position. The length of the pendulum is 10 m. If it dissipates 10% of its initial energy against air resistance, the speed with which the bob arrives at the lowest point is: [Use, g : 10 m s]
- A. m s
- B. m s
- C. m s
- D. m s
Correct answer: A
Explanation: .
Question 42
Physics · 4 marks · −1A physical quantity is found to depend on quantities a, b, c by the relation . The percentage error in a, b and c are 3%, 4% and 5% respectively. Then, the percentage error in Q is:
- A.43%
- B.66%
- C.34%
- D.14%
Correct answer: C
Explanation: .
Question 43
Physics · 4 marks · −1Given below are two statements: Statement I : Most of the mass of the atom and all its positive charge are concentrated in a tiny nucleus and the electrons revolve around it, is Rutherford's model. Statement II : An atom is a spherical cloud of positive charges with electrons embedded in it, is a special case of Rutherford's model. In the light of the above statements, choose the most appropriate from the options given below.
- A.Statement I is false but Statement II is true
- B.Statement I is true but Statement II is false
- C.Both Statement I and Statement II are true
- D.Both statement I and statement II are false
Correct answer: B
Explanation: Statement II describes Thomson's model.
Question 44
Physics · 4 marks · −1A stone of mass 900 g is tied to a string and moved in a vertical circle of radius 1 m making 10 rpm. The tension in the string, when the stone is at the lowest point is (if and m/s²):
- A.9.8 N
- B.8.82 N
- C.97 N
- D.17.8 N
Correct answer: A
Explanation: ; N.
Question 45
Physics · 4 marks · −1A small liquid drop of radius R is divided into 27 identical liquid drops. If the surface tension is T, then the work done in the process will be:
- A.
- B.
- C.
- D.
Correct answer: C
Explanation: Area grows from to .
Question 46
Physics · 4 marks · −1Two sources of light emit with a power of 200 W. The ratio of number of photons of visible light emitted by each source having wavelengths 300 nm and 500 nm respectively, will be:
- A.1 : 3
- B.1 : 5
- C.5 : 3
- D.3 : 5
Correct answer: D
Explanation: at fixed power.
Question 47
Physics · 4 marks · −1The temperature of a gas having molecules per cubic meter at 1.38 atm (Given, J K)
- A.100 K
- B.300 K
- C.200 K
- D.500 K
Correct answer: D
Explanation: K.
Question 48
Physics · 4 marks · −1A planet takes 200 days to complete one revolution around the Sun. If the distance of the planet from Sun is reduced to one fourth of the original distance, how many days will it take to complete one revolution:
- A.25
- B.50
- C.20
- D.100
Correct answer: A
Explanation: : .
Question 49
Physics · 4 marks · −1A particle is moving in a straight line. The variation of position 'x' as a function of time 't' is given as m. The velocity of the body when its acceleration becomes zero is:
- A.4 m/s
- B.6 m/s
- C.8 m/s
- D.10 m/s
Correct answer: C
Explanation: ; m/s.
Question 50
Physics · 4 marks · −1In an a.c. circuit, voltage and current are given by: V and mA respectively. The average power dissipated in one cycle is:
- A.2.5 W
- B.10 W
- C.5 W
- D.25 W
Correct answer: A
Explanation: W.
Question 51
Physics · 4 marks · −1In the given figure, the charge stored in 6 μF capacitor. when points A and B are joined by a connecting wire is ______ μC.

Correct answer: 36
Explanation: Steady state: current flows 9 V → 6 Ω → A–B → 3 Ω → ground, A, V; the 6 μF capacitor has 6 V across it: μC.
Question 52
Physics · 4 marks · −1Two metallic wires P and Q have same volume and are made up of same material. If their area of cross sections are in the ratio 4: 1 and force is applied to P, an extension of is produced. The force which is required to produce same extension in Q is . The value of is ______.
Correct answer: 16
Explanation: at fixed volume: ratio 16.
Question 53
Physics · 4 marks · −1In the given circuit, the current flowing through the resistance 20 Ω is 0.3 A, while the ammeter reads 0.9 A. The value of is ______ Ω.

Correct answer: 30
Explanation: V; 15 Ω carries 0.4 A, so carries 0.2 A: .
Question 54
Physics · 4 marks · −1A simple harmonic oscillator has an amplitude A and time period second. Assuming the oscillation starts from its mean position. the time required by it to travel from to will be s, where ______.
Correct answer: 2
Explanation: ; .
Question 55
Physics · 4 marks · −1In a single slit diffraction pattern, a light of wavelength 6000 Å is used. The distance between the first and third minima in the diffraction pattern is found to be 3 mm when the screen in placed 50 cm away from slits. The width of the slit is ______ m.
Correct answer: 2
Explanation: m.
Question 56
Physics · 4 marks · −1A particle is moving in a circle of radius 50 cm in such a way that at any instant the normal and tangential components of it's acceleration are equal. If its speed at is 4 m/s, the time taken to complete the first revolution will be s, where ______.
Correct answer: 8
Explanation: gives and ; gives .
Question 57
Physics · 4 marks · −1A charge of 4.0 μC is moving with a velocity of m s along the positive y-axis under a magnetic field of strength T. The force acting on the charge is N. The value of is ______.
Correct answer: 32
Explanation: N.
Question 58
Physics · 4 marks · −1A horizontal straight wire 5 m long extending from east to west falling freely at right angle to horizontal component of earths magnetic field Wb m. The instantaneous value of emf induced in the wire when its velocity is 10 m s is ______ V.
Correct answer: 3
Explanation: V.
Question 59
Physics · 4 marks · −1A body of mass 5 kg moving with a uniform speed m s in X-Y plane along the line . The angular momentum of the particle about the origin will be ______ kg m² s.
Correct answer: 60
Explanation: Perpendicular distance of the line from O is ; .
Question 60
Physics · 4 marks · −1Hydrogen atom is bombarded with electrons accelerated through a potential difference of V, which causes excitation of hydrogen atoms. If the experiment is being performed at T = 0 K, the minimum potential difference needed to observe any Balmer series lines in the emission spectra will be V, where ______.
Correct answer: 121
Explanation: Excitation to needs 12.09 eV ≈ 12.1 V.
Question 61
Chemistry · 4 marks · −1According to IUPAC system, the compound (cyclohexene ring bearing OH on the carbon adjacent to the C=C, as shown) is named as:
- A.Cyclohex-1-en-2-ol
- B.Cyclohex-1-en-3-ol
- C.Cyclohex-2-en-1-ol
- D.1-Hydroxyhex-2-ene
Correct answer: C
Question 62
Chemistry · 4 marks · −1Match List I with List II. List I (Spectral Series for Hydrogen): A. Lyman; B. Balmer; C. Paschen; D. Pfund List II (Spectral Region/Higher Energy State): I. Infrared region; II. UV region; III. Infrared region; IV. Visible region Choose the correct answer from the options given below:
- A.A-I, B-II, C-III, D-IV
- B.A-I, B-III, C-II, D-IV
- C.A-II, B-IV, C-III, D-I
- D.A-II, B-III, C-I, D-IV
Correct answer: C
Question 63
Chemistry · 4 marks · −1Alkyl halide is converted into alkyl isocyanide by reaction with:
- A.
- B.AgCN
- C.KCN
- D.NaCN
Correct answer: B
Question 64
Chemistry · 4 marks · −1Match List I with List II. List I (Compound): A. Ethanol; B. Phenol; C. m-Nitrophenol; D. p-Nitrophenol List II ( Value): I. 10.0; II. 15.9; III. 7.1; IV. 8.3 Choose the correct answer from the options given below:
- A.A-II, B-I, C-IV, D-III
- B.A-IV, B-I, C-II, D-III
- C.A-I, B-II, C-III, D-IV
- D.A-III, B-IV, C-I, D-II
Correct answer: A
Question 65
Chemistry · 4 marks · −1A reagent which gives brilliant red precipitate with Nickel ions in basic medium is:
- A.dimethyl glyoxime
- B.sodium nitroprusside
- C.meta-dinitrobenzene
- D.neutral
Correct answer: A
Question 66
Chemistry · 4 marks · −1Given below are two statements: Statement I : Fluorine has most negative electron gain enthalpy in its group. Statement II : Oxygen has least negative electron gain enthalpy in its group. In the light of the above statements, choose the most appropriate from the options given below:
- A.Statement I is false but Statement II is true
- B.Statement I is true but Statement II is false
- C.Both Statement I and Statement II are true
- D.Both Statement I and Statement II are false
Correct answer: A
Explanation: Chlorine, not fluorine, has the most negative electron gain enthalpy in group 17.
Question 67
Chemistry · 4 marks · −1Which of the following acts as a strong reducing agent? (Atomic number: Ce = 58, Eu = 63, Gd = 64, Lu = 71)
- A.
- B.
- C.
- D.
Correct answer: D
Question 68
Chemistry · 4 marks · −1Which of the following reaction is correct?
- A.
- B.Cyclohexene 1,2-dibromocyclohexane
- C.
- D.1-Methylcyclohexene HI 1-iodo-1-methylcyclohexane
Correct answer: D
Explanation: Markovnikov addition of HI; the others give wrong products (Hofmann gives CHNH; UV/Δ gives allylic bromide; propylamine gives propanol).
Question 69
Chemistry · 4 marks · −1On passing a gas, 'X', through Nessler's reagent, a brown precipitate is obtained. The gas 'X' is:
- A.
- B.
- C.
- D.
Correct answer: C
Question 70
Chemistry · 4 marks · −1Match List I with List II. List I (Bio polymer): A. Starch; B. Cellulose; C. Nucleic acid; D. Protein List II (Monomer): I. nucleotide; II. α-glucose; III. β-glucose; IV. α-amino acid Choose the correct answer from the options given below:
- A.A-I, B-III, C-IV, D-II
- B.A-II, B-I, C-III, D-IV
- C.A-IV, B-II, C-I, D-III
- D.A-II, B-III, C-I, D-IV
Correct answer: D
Question 71
Chemistry · 4 marks · −1Which one of the following will show geometrical isomerism?

- A.4-Bromo-1-methylidenecyclohexane (=CH exocyclic, Br para)
- B.3-Bromo-1-(bromomethylidene)cyclohexane (=CHBr exocyclic, Br meta)
- C.4-Bromo-1-(bromomethylidene)cyclohexane (=CHBr exocyclic, Br para)
- D.3-Bromo-1-methylidenecyclohexane (=CH exocyclic, Br meta)
Correct answer: B
Explanation: Only with =CHBr and an unsymmetrically substituted ring (Br at C-3) are the two ends of the double bond each differently substituted.
Question 72
Chemistry · 4 marks · −1The correct IUPAC name of is:
- A.Potassium tetraoxidomanganate (VI)
- B.Dipotassium tetraoxidomanganate (VII)
- C.Potassium tetraoxopermanganate (VI)
- D.Potassium tetraoxidomanganese (VI)
Correct answer: A
Question 73
Chemistry · 4 marks · −1Phenol treated with chloroform in presence of sodium hydroxide, which further hydrolyzed in presence of an acid results.
- A.Benzene-1,2-diol
- B.2-Hydroxybenzaldehyde
- C.Benzene-1,3-diol
- D.Salicylic acid
Correct answer: B
Explanation: Reimer–Tiemann reaction.
Question 74
Chemistry · 4 marks · −1Chromatographic technique/s based on the principle of differential adsorption is/are: A. Column chromatography B. Thin layer chromatography C. Paper chromatography Choose the most appropriate answer from the options given below:
- A.A only
- B.A and B only
- C.B only
- D.C only
Correct answer: B
Explanation: Paper chromatography is partition chromatography.
Question 75
Chemistry · 4 marks · −1The product A formed in the following reaction is: Aniline A
- A.Chlorobenzene
- B.Anilinium chloride ()
- C.1,2-Dichlorobenzene
- D.2-Chloroaniline
Correct answer: A
Explanation: Diazotisation followed by Sandmeyer reaction.
Question 76
Chemistry · 4 marks · −1The element having the highest first ionization enthalpy is:
- A.N
- B.Al
- C.Si
- D.C
Correct answer: A
Question 77
Chemistry · 4 marks · −1Identify the reagents used for the following conversion. A keto-ester-aldehyde bicyclic precursor (a cyclohexane ring bearing OH, a arm and a arm) the dialdehyde a bicyclic α,β-unsaturated aldehyde (with OH) a bicyclic diene bearing a methyl group (OH removed)

- A.A = , B = , C = Zn/HCl
- B.A = DIBAL – H, B = , C = Zn/HCl
- C.A = DIBAL – H, B = , C = /KOH, ethylene glycol
- D.A = , B = , C = /KOH, ethylene glycol
Correct answer: B
Explanation: DIBAL-H reduces the ester only to the aldehyde; alcoholic NaOH effects aldol condensation; Clemmensen (Zn/HCl) reduces CHO to CH while the acid dehydrates the alcohol.
Question 78
Chemistry · 4 marks · −1The ascending acidity order of the following H atoms is: A: ; B: ; C: ; D:
- A.C < D < B < A
- B.D < C < B < A
- C.A < B < C < D
- D.A < B < D < C
Correct answer: A
Explanation: sp C–H > sp C–H > 1° sp > 3° sp.
Question 79
Chemistry · 4 marks · −1Which of the following statements are correct about Zn, Cd and Hg? A. They exhibit high enthalpy of atomization as the d-subshell is full. B. Zn and Cd do not show variable oxidation state while Hg shows +I and +II. C. Compounds of Zn, Cd and Hg are paramagnetic in nature. D. Zn, Cd and Hg are called soft metals. Choose the most appropriate from the options given below:
- A.A, D only
- B.B, D only
- C.C, D only
- D.B, C only
Correct answer: B
Question 80
Chemistry · 4 marks · −1Anomalous behavior of oxygen is due to its:
- A.small size and high electronegativity
- B.small size and low electronegativity
- C.large size and high electronegativity
- D.large size and low electronegativity
Correct answer: A
Question 81
Chemistry · 4 marks · −1If 50 mL of 0.5M oxalic acid is required to neutralise 25 mL of NaOH solution, the amount of NaOH in 50 mL of given NaOH solution is ______ g.
Correct answer: 4
Explanation: 0.025 mol oxalic acid needs 0.05 mol NaOH in 25 mL (2 M); 50 mL holds 0.1 mol = 4 g.
Question 82
Chemistry · 4 marks · −1A constant current was passed through a solution of ion between gold electrodes. After a period of 10.0 minutes, the increase in mass of cathode was 1.314 g. The total charge passed through the solution is ______ F. (Given atomic mass of Au = 197)
Correct answer: 2
Explanation: F.
Question 83
Chemistry · 4 marks · −1The following concentrations were observed at 500 K for the formation of from and . At equilibrium: M, M and M. Equilibrium constant for the reaction is ______.
Correct answer: 417
Explanation: .
Question 84
Chemistry · 4 marks · −1The total number of anti bonding molecular orbitals, formed from 2s and 2p atomic orbitals in a diatomic molecule is ______.
Correct answer: 4
Explanation: , , , .
Question 85
Chemistry · 4 marks · −1Standard enthalpy of vapourisation for is 30.5 kJ mol. Heat required for vapourisation of 284 g of at constant temperature is ______ kJ. (Given molar mass in g mol: C = 12, Cl = 35.5)
Correct answer: 56
Explanation: kJ.
Question 86
Chemistry · 4 marks · −1The total number of 'Sigma' and 'Pi' bonds in 2-formylhex-4-enoic acid is ______.
Correct answer: 22
Question 87
Chemistry · 4 marks · −1The oxidation number of iron in the compound formed during brown ring test for ion is ______.
Correct answer: 1
Explanation: with NO: Fe is +1.
Question 88
Chemistry · 4 marks · −1The total number of molecules with zero dipole moment among , , , HF, , and is ______.
Correct answer: 3
Explanation: CH, BF, CO.
Question 89
Chemistry · 4 marks · −1The half-life of radioisotope bromine – 82 is 36 hours. The fraction which remains after one day is ______ . (Given antilog 0.2006 = 1.587)
Correct answer: 63
Explanation: .
Question 90
Chemistry · 4 marks · −1Molality of 0.8 M solution (density 1.06 g cm) is ______ m.
Correct answer: 815
Explanation: 1 L = 1060 g, solute 78.4 g, solvent 981.6 g; .