NEET 2025 Chemistry Questions

The correct order of decreasing acidity of the following aliphatic acids is:

Which one of the following reactions does NOT belong to Lassaigne's test?

How many products (including stereoisomers) are expected from the monochlorination of 2-methylbutane, $\ce{(CH3)2CH-CH2-CH3}$?

The total number of possible isomers (both structural as well as stereoisomers) of cyclic ethers of molecular formula $\ce{C4H8O}$ is:

Among the given compounds I-III, the correct order of bond dissociation energy of the C-H bond marked with an asterisk (*) is:

The correct order of decreasing basic strength of the given amines is:

Match List I (Mixture) with List II (Method of Separation). List I A. $\ce{CHCl3}$ + $\ce{C6H5NH2}$ B. Crude oil in the petroleum industry C. Glycerol from spent-lye D. Aniline-water List II I. Distillation under reduced pressure II. Steam distillation III. Fractional distillation IV. Simple distillation

Which one of the following compounds can exist as cis-trans isomers?

Which one of the following reactions does NOT give benzene as the product?

How many products (including stereoisomers) are expected from monochlorination of 2-methylbutane, \ce{(CH3)2CH-CH2-CH3}?

Among the compounds I, II and III shown, the correct order of bond dissociation energy of the C–H bond marked with $*$ is: (I) benzene, aryl (sp$^2$) C–H; (II) phenylacetylene \ce{C6H5-C#C-H}, terminal alkynyl (sp) C–H; (III) 3-methylenecyclopropane / cyclopropene bearing an exocyclic \ce{CH2}, the methylene (sp$^3$) C–H.

Which one of the following compounds does NOT decolourize bromine water?

Which one of the following compounds can exist as cis-trans isomers?

The ratio of the wavelengths of the light absorbed by a hydrogen atom when it undergoes $n=2 \rightarrow n=3$ and $n=4 \rightarrow n=6$ transitions, respectively, is:

Energy and radius of the ground-state Bohr orbit of \ce{He+} and \ce{Li^2+} are: [Given $R_H = 2.18 \times 10^{-18}$ J, $a_0 = 52.9$ pm]

Dalton's atomic theory could not explain which of the following?

Which among the following electronic configurations belong to main-group elements? A. $[\ce{Ne}]3s^{1}$ B. $[\ce{Ar}]3d^{3}\,4s^{2}$ C. $[\ce{Kr}]4d^{10}\,5s^{2}\,5p^{5}$ D. $[\ce{Ar}]3d^{10}\,4s^{1}$ E. $[\ce{Rn}]5f^{0}\,6d^{2}\,7s^{2}$

The standard heat of formation, in $\text{kcal\,mol}^{-1}$, of $\ce{Ba^2+}$ is: [Given: standard heat of formation of $\ce{SO4^2-}$ ion (aq) $= -216\ \text{kcal\,mol}^{-1}$, standard heat of crystallisation of $\ce{BaSO4(s)} = -4.5\ \text{kcal\,mol}^{-1}$, standard heat of formation of $\ce{BaSO4(s)} = -349\ \text{kcal\,mol}^{-1}$]

$\ce{C(s) + 2H2(g) -> CH4(g)}$; $\Delta H = -74.8\ kJ\,mol^{-1}$. Which of the following diagrams gives an accurate representation of the above reaction? [R $\rightarrow$ reactants; P $\rightarrow$ products]

Which of the following statements are true? A. Unlike \ce{Ga}, that has a very high melting point, \ce{Cs} has a very low melting point. B. On the Pauling scale, the electronegativity values of \ce{N} and \ce{Cl} are not the same. C. \ce{Ar}, \ce{K+}, \ce{Cl-}, \ce{Ca^2+} and \ce{S^2-} are all isoelectronic species. D. The correct order of the first ionization enthalpies of \ce{Na}, \ce{Mg}, \ce{Al} and \ce{Si} is $\text{Si} > \text{Al} > \text{Mg} > \text{Na}$. E. The atomic radius of \ce{Cs} is greater than that of \ce{Li} and \ce{Rb}.

Which among the following electronic configurations belong to main group elements? A. $[\text{Ne}]3s^1$ B. $[\text{Ar}]3d^3\,4s^2$ C. $[\text{Kr}]4d^{10}\,5s^2\,5p^5$ D. $[\text{Ar}]3d^{10}\,4s^1$ E. $[\text{Rn}]5f^0\,6d^2\,7s^2$

Among the following, choose the ones with an equal number of atoms. A. 212 g of \ce{Na2CO3}(s) [molar mass = 106 g] B. 248 g of \ce{Na2O}(s) [molar mass = 62 g] C. 240 g of \ce{NaOH}(s) [molar mass = 40 g] D. 12 g of \ce{H2}(g) [molar mass = 2 g] E. 220 g of \ce{CO2}(g) [molar mass = 44 g] Choose the correct answer from the options given below:

Dalton's atomic theory could \emph{not} explain which of the following?

Match List-I with List-II. List-I: A. \ce{XeO3}; B. \ce{XeF2}; C. \ce{XeOF4}; D. \ce{XeF6} List-II: I. $sp^3d$; linear; II. $sp^3$; pyramidal; III. $sp^3d^3$; distorted octahedral; IV. $sp^3d^2$; square pyramidal Choose the correct answer from the options given below:

Identify the correct orders against the property mentioned: A. \ce{H2O} > \ce{NH3} > \ce{CHCl3} — dipole moment B. \ce{XeF4} > \ce{XeO3} > \ce{XeF2} — number of lone pairs on central atom C. \ce{O-H} > \ce{C-H} > \ce{N-O} — bond length D. \ce{N2} > \ce{O2} > \ce{H2} — bond enthalpy Choose the answer from the options given below:

Consider the following compounds: \ce{KO2}, \ce{H2O2} and \ce{H2SO4}. The oxidation states of the underlined elements (\ce{K} in \ce{KO2}, \ce{O} in \ce{H2O2}, \ce{S} in \ce{H2SO4}) in them are, respectively,

Identify the suitable reagent for the following conversion: \ce{C6H5COOCH3 -> C6H5CHO} (methyl benzoate to benzaldehyde)

The correct order of decreasing acidity of the following aliphatic acids is

The major product of the following reaction is: 4-oxo-4-phenylbutanenitrile \ce{C6H5-CO-CH2-CH2-CN} is treated with (i) \ce{CH3MgBr} (excess) and then (ii) \ce{H3O+}.

Out of the following complex compounds, which compound will have the minimum conductance in solution?

Which of the following are paramagnetic? A. \ce{[NiCl4]^2-} B. \ce{Ni(CO)4} C. \ce{[Ni(CN)4]^2-} D. \ce{[Ni(H2O)6]^2+} E. \ce{Ni(PPh3)4}

The correct order of the wavelength of light absorbed by the following complexes is: A. $\ce{[Co(NH3)6]^3+}$ B. $\ce{[Co(CN)6]^3-}$ C. $\ce{[Cu(H2O)4]^2+}$ D. $\ce{[Ti(H2O)6]^3+}$

The correct order of decreasing basic strength of the given amines is: (N-ethylethanamine $=$ \ce{(C2H5)2NH}; ethanamine $=$ \ce{C2H5NH2}; N-methylaniline $=$ \ce{C6H5NH(CH3)}; benzenamine/aniline $=$ \ce{C6H5NH2})

Predict the major product $P$ in the following sequence of reactions. The starting material is 1-methylcyclopent-1-ene: (i) \ce{HBr}, benzoyl peroxide; (ii) \ce{KCN}; (iii) \ce{Na(Hg)}/\ce{C2H5OH} $\rightarrow$ $P$ (major). The structures of the options (A)-(D) are shown in the image below:

Given below are two statements. Statement I: Benzenediazonium salt is prepared by the reaction of aniline with acid at 273-278 K. It decomposes easily in the dry state. Statement II: Insertion of iodine into the benzene ring is difficult, and hence iodobenzene is prepared through the reaction of the benzenediazonium salt with \ce{KI}. In the light of the above statements, choose the most appropriate answer.

Sugar 'X': A. is found in honey B. is a keto sugar C. exists in α and β anomeric forms D. is laevorotatory 'X' is

Match List I with List II. List I (Name of Vitamin) A. Vitamin B12 B. Vitamin D C. Vitamin B2 D. Vitamin B6 List II (Deficiency disease) I. Cheilosis II. Convulsions III. Rickets IV. Pernicious anaemia Choose the correct answer from the options given below:

Which of the following aqueous solution will exhibit highest boiling point?

5 moles of liquid X and 10 moles of liquid Y make a solution having a vapour pressure of 70 torr. The vapour pressures of pure X and Y are 63 torr and 78 torr respectively. Which of the following is true regarding the described solution?

Given below are two statements: one labelled Assertion (A) and the other Reason (R). Assertion (A): $\ce{CH3CH2CH2I}$ (n-propyl iodide) undergoes $\ce{S_N2}$ reaction faster than $\ce{CH3CH2CH2Cl}$ (n-propyl chloride). Reason (R): Iodine is a better leaving group because of its large size. In the light of the above statements, choose the correct answer from the options given below.

Given below are two statements: Statement I: Benzenediazonium salt is prepared by the reaction of aniline with acid at 273-278 K. It decomposes easily in the dry state. Statement II: Insertion of iodine into the benzene ring is difficult and hence iodobenzene is prepared through the reaction of benzenediazonium salt with KI. In the light of the above statements, choose the most appropriate answer from the options given below:

If the rate constant of a reaction is $0.03\ \text{s}^{-1}$, how much time does it take for $7.2\ \text{mol L}^{-1}$ concentration of the reactant to get reduced to $0.9\ \text{mol L}^{-1}$? (Given: $\log 2 = 0.301$)

If the half-life $t_{1/2}$ for a first order reaction is $1$ minute, then the time required for $99.9\%$ completion of the reaction is closest to

The total number of possible isomers (both structural as well as stereoisomers) of cyclic ethers of molecular formula \ce{C4H8O} is:

Given below are two statements: Statement I: Ferromagnetism is considered as an extreme form of paramagnetism. Statement II: The number of unpaired electrons in a \ce{Cr^2+} ion (Z = 24) is the same as that of a \ce{Nd^3+} ion (Z = 60). In the light of the above statements, choose the correct answer from the options given below:

If the molar conductivity ($\Lambda_m$) of a $0.050\ \text{mol L}^{-1}$ solution of a monobasic weak acid is $90\ \text{S cm}^2\,\text{mol}^{-1}$, its extent (degree) of dissociation will be [Assume $\lambda^\circ_+ = 349.6\ \text{S cm}^2\,\text{mol}^{-1}$ and $\lambda^\circ_- = 50.4\ \text{S cm}^2\,\text{mol}^{-1}$]