NEET 2026 Chemistry Questions

Identify the incorrect statement related to \ce{PCl5} from the following:

Match the species in List-I with their geometry in List-II. List-I: A. $\ce{PCl5}$, B. $\ce{BrF5}$, C. $\ce{BF4-}$, D. $\ce{[Ni(CN)4]^{2-}}$. List-II: I. Tetrahedral, II. Square planar, III. Trigonal bipyramidal, IV. Square pyramidal.

The correct statement is:

Identify the correct statement about \ce{ClF3} from the following options:

For the ozone (\ce{O3}) Lewis structure shown in the figure — a central O atom (1) doubly bonded to one terminal O atom (2) and singly bonded to the other terminal O atom (3) — the correct formal charges on the oxygen atoms numbered 2, 1 and 3 respectively are:

The highest occupied molecular orbital for $\ce{Ne2}$ is:

For the reversible processes of 1 mol of an ideal gas shown (a cycle $p_1V_1T_1\to p_2V_2T_1$ [process 1, isothermal] $\to p_3V_3T_2$ [process 2, adiabatic] $\to p_4V_4T_2$ [process 3, isothermal] $\to$ back [process 4, adiabatic]), with $w_1,w_2,w_3,w_4$ the work done (in calories) and $\Delta U_2,\Delta U_4$ the internal-energy changes in processes 2 and 4. [Use $R=2\,\text{cal K}^{-1}\text{mol}^{-1}$.] The correct option is:

Consider the following reaction: $\ce{2A(g) + B(g) -> 2D(g)}$ $\Delta U^\circ = -10\ kJ\,mol^{-1}$ and $\Delta S^\circ = -44\ J\,K^{-1}$ at $298\ \text{K}$. Identify the correct option with $\Delta G^\circ$ for the reaction and the spontaneity of the reaction at $298\ \text{K}$. (Given: $R = 8.31\ J\,mol^{-1}K^{-1}$)

At a certain temperature $T$ (K), during a process, $500\ \text{J}$ is absorbed by the system and work of $200\ \text{J}$ is done by the system. Then the change in internal energy of the system is:

Two moles of an ideal gas undergo free expansion from $10\,$L to $100\,$L at $300\,$K. The values of $\Delta S_{system}$ and $\Delta S_{surroundings}$ are (R = universal gas constant):

A protein undergoes reversible thermal denaturation $N\rightleftharpoons D$. At $60\,^\circ$C the concentrations of $N$ and $D$ are equal at equilibrium, and the standard enthalpy change of denaturation is $666\,\text{kJ mol}^{-1}$. The standard entropy change $\Delta S^\circ$ (in $\text{kJ K}^{-1}\text{mol}^{-1}$) of the protein upon denaturation at $60\,^\circ$C is closest to:

The correct IUPAC name of the following compound is:

Among the following, the compound having conjugated double bonds is:

Consider the reaction sequences and choose the correct option. $Ph\text{-}C\equiv C\text{-}Me$ with $\ce{Na}$/liq. $\ce{NH3}\to L$; with $\ce{H2}$, Pd/C (Lindlar's catalyst) $\to K$. Then $L\xrightarrow{\text{HBr, benzoyl peroxide}}N$ and $K\xrightarrow{\text{HBr}}M$.

Statement-I: trans-But-2-ene on treatment with $\ce{Br2}$ in $\ce{CCl4}$ gives the shown product (a meso-2,3-dibromobutane). Statement-II: cis-But-2-ene on treatment with alkaline $\ce{KMnO4}$ gives the shown product (meso-butane-2,3-diol). Choose the most appropriate answer:

The number of chlorine atoms present in the organic products X and Y of the following reactions, respectively, are: \ce{C6H6 + 6Cl2 ->[\text{anhyd. }AlCl3][\text{dark, cold}] X} and \ce{C6H6 + 3Cl2 ->[\text{UV}][500\,K] Y}

Identify the incorrect statement from the following:

Assertion A: The first ionization enthalpy of O is lower than that of N and F. Reason R: The loss of an electron from O leads to a stable half-filled $p$ orbital. Choose the most appropriate answer:

Among the following, the correct trend in electron gain enthalpy (most negative first) is:

The correct order of increasing metallic character of \ce{Na}, \ce{Be}, \ce{P}, \ce{Mg} and \ce{Si} is:

The numbers $17.0145$ and $21.0235$ were rounded to three figures after the decimal point. The resulting numbers, respectively, are:

The number of hydrogen atoms present in 5.4 g of urea is (molar mass of urea = 60 g mol$^{-1}$; $N_A = 6.022\times10^{23}$ mol$^{-1}$)

When 1 dm$^3$ of \ce{CO2} gas is passed over hot coke, the volume of the gaseous mixture after complete reaction at STP becomes 1.4 dm$^3$. The composition of the gaseous mixture at STP is

The amount of carbon dioxide evolved upon complete combustion of $116\,$g of n-butane is: (Atomic masses: H $=1$, C $=12$, O $=16$)

The correct IUPAC name of the following compound is:

The carbocation $\ce{C6H5-\overset{+}{C}H-CH3}$ (1-phenylethyl cation) is stabilized by the interaction of the empty $p$ orbital with:

The pair of molecules that are metamers among the following is:

During Lassaigne's test, the elements present in an organic compound are converted from:

The calculated 'spin-only' magnetic moment of \ce{Ti^2+} ($3d^{2}$) is:

Consider the schematic plots of the orbital wavefunction $\psi_r$ against distance $r$ from the nucleus (A: monotonically decreasing; B: one sign-change; C: two ripples crossing zero twice; D: oscillatory). The figure representing two radial nodes in the orbital is:

Match List-I with List-II: List-I ($n$, $l$) (A) $n=2$, $l=1$ (B) $n=4$, $l=0$ (C) $n=5$, $l=3$ (D) $n=3$, $l=2$ List-II (Orbital) (I) $3d$ (II) $2p$ (III) $4s$ (IV) $5f$ Choose the correct answer from the options given below:

A bulb is rated at $150$ watt, converting $8\%$ of its energy into light. If the energy of one photon is $4.42 \times 10^{-19}$ J, how many photons are emitted by the bulb per second?

Identify the incorrect statement from the following:

The correct decreasing order of oxidation state of the underlined atom in each molecule is:

In acidic medium, $10\,$mL of $0.25\,$M oxalic acid is titrated with $\ce{KMnO4}$ solution. If the volume of $\ce{KMnO4}$ required to reach the end point is $10\,$mL, the strength of the $\ce{KMnO4}$ solution is:

The calculated spin only magnetic moment of $\ce{Cr^2+}$ ion is:

The calculated 'spin-only' magnetic moment of $\ce{Ti^2+}$ ($3d^2$) is:

The complex which has facial and meridional isomers is: (py = pyridine, en = $\ce{H2N-CH2-CH2-NH2}$)

Given two statements — Statement-I: $\ce{[Fe(ox)3]^{3-}}$ is chiral. Statement-II: $trans\text{-}\ce{[Cr(H2O)2(ox)2]^-}$ is chiral. (oxH$_2$ = HOOC–COOH). Choose the most appropriate answer:

According to crystal field theory, the correct order of ligands with respect to their decreasing field strength is:

A $1:3$ electrolyte in aqueous solution is:

Match List-I (Complex) with List-II (Type of isomerism): List-I (a) \ce{[Pt(NH3)2Cl2]} (b) \ce{[Co(en)3]^3+} (c) \ce{[Co(NH3)5(NO2)]Cl2} (d) \ce{[Cr(H2O)6]Cl3} List-II (i) Optical (ii) Solvate (iii) Geometrical (iv) Linkage Choose the correct option:

Which one of the following is an ambidentate ligand?

Match List-I (Complex/ion) with List-II (Shape/geometry): List-I (a) \ce{[PtCl2(NH3)2]} (b) \ce{[Co(NH3)6]Cl3} (c) \ce{[NiCl4]^2-} (d) \ce{[Fe(CO)5]} List-II (i) Octahedral (ii) Trigonal bipyramidal (iii) Square planar (iv) Tetrahedral Choose the correct option:

Among the species below, the spin-only magnetic moment is highest for: (Atomic numbers: Ti $=22$, Mn $=25$, Fe $=26$, Co $=27$)

The formula of tetraammineaquachloridocobalt(III) chloride is:

In potash alum, the ratio of $\ce{K+}$ and $\ce{SO4^{2-}}$ ions is:

The calculated spin only magnetic moment of \ce{Cr^2+} ion is:

The calculated 'spin-only' magnetic moment of \ce{Ti^2+} (\ce{3d^2}) is:

Statement-I: Heating $\ce{NaCl}$ with concentrated $\ce{H2SO4}$ and $\ce{MnO2}$ results in oxidation of Mn. Statement-II: Heating $\ce{NaI}$ with concentrated $\ce{H2SO4}$ and $\ce{MnO2}$ results in reduction of Mn. Choose the most appropriate answer:

Assertion A: Generally, $3d$ transition metals have high melting points. Reason R: Involvement of $3d$-electrons in addition to $4s$-electrons in the interatomic metallic bonding. Choose the most appropriate answer:

The lanthanide ion having four unpaired electrons is: (Atomic numbers: Ce $=58$, Nd $=60$, Tb $=65$, Ho $=67$)

Match List I with List II: List I (Transition metal/compound/complex) (a) \ce{V2O5} (b) \ce{Fe} (c) \ce{PdCl2} (d) Ni complex List II (Catalytic Role) (i) Preparation of ammonia from \ce{N2}/\ce{H2} mixture (ii) Polymerisation of alkynes (iii) Preparation of \ce{H2SO4} and \ce{SO2} (iv) Oxidation of ethyne to ethanal Choose the correct answer from the options given below:

Although the +3 oxidation state is most common in lanthanoids, cerium still shows the +4 oxidation state because:

The green paramagnetic species formed by heating $\ce{KMnO4}$ at $513\,$K is:

Consider the reaction: toluene $\xrightarrow{\text{(i) }\ce{CrO2Cl2},\,\ce{CS2}}\xrightarrow{\text{(ii) }\ce{H3O+}} P$. Choose the correct option about $P$.

The compound that CANNOT be obtained from the aldol condensation reaction shown (2,2-dimethylcyclopentanone $+\ \ce{PhCHO} \xrightarrow{\text{NaOH},\,\Delta}$) is:

Statement-I: Oxidation of p-nitrotoluene with acidic $\ce{KMnO4}$ gives an acid that is stronger than benzoic acid. Statement-II: Reduction of p-nitrotoluene with Sn/HCl followed by neutralization gives an amine that is more basic than aniline. Choose the most appropriate answer:

Compound $P$ (\ce{C8H8O}) gives a red-orange precipitate with 2,4-DNP reagent and does not reduce Fehling's reagent. On drastic oxidation with chromic acid, $P$ gives an aromatic product $Q$ that produces effervescence on treatment with aq. \ce{NaHCO3}. Compounds $P$ and $Q$ respectively are:

For the following reaction sequence, choose the correct option. Benzene $\xrightarrow{\text{(i) }\ce{CH3COCl},\ \ce{AlCl3}}\ \xrightarrow{\text{(ii) NaOCl}}\ P+Q$

Arrange the following compounds in the increasing order of polarity: A. $\ce{CH3CH2OCH2CH3}$, B. $\ce{CH3CH2OH}$, C. $\ce{CH3COCH3}$, D. $\ce{CH3COOH}$.

One of the products formed in the following reaction is: cyclohexyl–$\ce{MgBr}$ + cyclohexyl–$\ce{NH2}\rightarrow$

The following two reactions give the same foul-smelling product $Z$. Reaction 1: $\ce{C2H5Cl + }X \ce{-> }Z$ Reaction 2: $\ce{C2H5CONH2 ->[Br2,\ NaOH]}$ $Y$ $\ce{->[\text{CHCl3 / ethanolic KOH}][\Delta]}$ $Z$ $X$ and $Z$, respectively, are :

In the following reaction sequence, $X$ and $Z$ respectively are : $\ce{CH3CH2CH2OH + PCl3 -> CH3CH2CH2Cl + }X \ce{ + HCl}$ $\ce{CH3CH2CH2Cl ->[\text{alc. KOH}][\Delta]}$ $Y$ $Y \ce{->[HBr][\text{peroxide}]}$ $Z$

The major product $Z$ formed in the following sequence of reactions is $\ce{C2H6 ->[Cl2][\text{UV}]}$ $X$ $\ce{->[NH3]}$ $Y$ $\ce{->[\text{(i) NaNO2/HCl}][\text{(ii) H2O}]}$ $Z$

The number of chlorine atoms present in the organic products $X$ and $Y$ of the following reactions, respectively, are : $\ce{C6H6 + 6 Cl2 ->[\text{anhyd. AlCl3}][\text{dark, cold}]}$ $X$ $\ce{C6H6 + 3 Cl2 ->[\text{UV}][\text{500 K}]}$ $Y$

$2A\xrightarrow{k}B$ is a zero-order reaction with $k=1.0\,\text{mol L}^{-1}\text{min}^{-1}$. If the initial concentration of $A$ is $2\,$M, the time taken to complete 75% of the reaction is:

For an elementary chemical reaction, the Arrhenius plot ($\ln k$ vs $1/T$) is given. If the activation energy is $6.64\,\text{kJ mol}^{-1}$ and $R=8.3\,\text{J K}^{-1}\text{mol}^{-1}$, the temperature at which the rate constant becomes $e^{2}\,\text{min}^{-1}$ is:

Match List I with List II : List-I (Order of reaction) (A) Zero order (B) First order (C) Second order (D) Third order List-II (Unit of rate constant) (I) $\text{mol}^{-1}\,\text{L}\,\text{s}^{-1}$ (II) $\text{mol}^{-2}\,\text{L}^2\,\text{s}^{-1}$ (III) $\text{s}^{-1}$ (IV) $\text{mol}\,\text{L}^{-1}\,\text{s}^{-1}$ Choose the correct answer from the options given below :

For a certain reaction \ce{R -> Product}, the plot of concentration $[R]$ versus time is a straight line with a constant negative slope, as shown in the graph. The order of the reaction is:

Given below is an expression for the rate constant of a first-order reaction occurring at a certain temperature $T$ (K): $\ln k = 14.34 - \frac{1.25\times10^{4}}{T}$ The energy of activation in $\text{kcal mol}^{-1}$ for the reaction is: (Given: $k$ in $\text{s}^{-1}$, $R=1.987\ \text{cal mol}^{-1}\,\text{K}^{-1}$)

Match the vitamins in List-I with their sources in List-II. List-I: A. vitamin A, B. vitamin $\ce{B12}$, C. vitamin E, D. vitamin K. List-II: I. meat, II. sunflower oil, III. green leafy vegetables, IV. carrots.

The correct statement with regard to the secondary structure of DNA/RNA is

The amino acid that gives a red-blood colour on treating its sodium fusion extract with sodium nitroprusside is:

The correct statement about peptides and proteins is:

Assertion A: For an ideal solution formed by mixing liquids $P$ and $Q$, $\Delta_{mix}H=0$ and $\Delta_{mix}V=0$. Reason R: No interactions occur between $P$ and $Q$. Choose the most appropriate answer:

Consider these statements about solutions formed by mixing two liquids: (A) An ideal solution obeys Raoult's law throughout the composition range. (B) A mixture of chloroform and acetone shows negative deviation from Raoult's law. (C) A mixture of aniline and phenol shows positive deviation from Raoult's law. The correct option is:

Identify the correct statements: (A) The molality of 2.5 g of ethanoic acid (Molar mass: $60\ \text{g mol}^{-1}$) in 75 g of benzene solution is 0.556 m. (B) The molarity of a solution containing 5 g of \ce{NaOH} (molar mass: $40\ \text{g mol}^{-1}$) in 450 mL of solution is 0.278 M at 298 K. (C) Aquatic species are more comfortable in cold water. (D) The solubility of a gas increases with decrease in pressure. (E) For a binary mixture of A and B, the number of moles of A and B are $n_A$ and $n_B$ respectively. The mole fraction of B will be $x_B = \frac{n_A}{n_A + n_B}$.

A mixture of chloroform and acetone forms a solution with negative deviation from Raoult's law due to:

The pair of molecules that are metamers among the following is:

Match List-I (organic transformation) with List-II (reagents) and choose the correct option. List-I A. \ce{C6H6 -> C6H5OH} (benzene to phenol) B. \ce{CH3COOH -> CH3CH2OH} C. \ce{CH3CH2CH2OH -> CH3CH=CH2} D. \ce{C6H5CH(CH3)2 -> C6H5OH} (cumene to phenol) List-II (I) (i) Oleum; (ii) \ce{NaOH}, heat; (iii) \ce{H+} (II) (i) \ce{O2}; (ii) \ce{H2O}/\ce{H+} (III) (i) \ce{CH3OH}, \ce{H+}; (ii) \ce{H2}, catalyst (IV) (i) conc. \ce{H2SO4}, heat; (ii) \ce{H+}/\ce{H2O}

The functional group that can be identified through the phthalein dye test is:

In the following reaction, two products X and Y are formed: \ce{C6H5OH ->[\text{conc. } HNO3][\text{conc. } H2SO4] X + Y} where X and Y are $o$-nitrophenol and $p$-nitrophenol. The suitable method that can be used for the separation of products X and Y is:

The standard electrode potential ($E^\circ$) for the half-cell reaction $\ce{Fe^{3+} + e^- -> Fe^{2+}}$ at 298 K is: [Given $E^\circ(\ce{Fe^{3+}/Fe})=-0.04\,$V and $E^\circ(\ce{Fe^{2+}/Fe})=-0.44\,$V]

A solution of copper sulphate is electrolysed for $10$ minutes with a current of $1.5$ amperes. The mass of copper deposited at the cathode is: (Given: Molar mass of \ce{Cu} $= 63$ g mol$^{-1}$; $1\,F = 96487$ C mol$^{-1}$)

Calculate the emf of the half cell given below: \ce{Pt(s) | H2(g, 2 atm) | HCl(aq, 0.02 M)} $E^\circ_{\ce{H+/H2}} = 0\ \text{V}$ (Given: $\frac{2.303RT}{F} = 0.059$, $\log 2 = 0.3010$)

For a strong electrolyte salt $XY$, the plot of $\Lambda_m$ versus $\sqrt{c}$ has slope $-90.0\,\text{S cm}^2\text{mol}^{-3/2}\text{L}^{1/2}$ at 298 K. At $0.01\,$M, $\Lambda_m=145.0\,\text{S cm}^2\text{mol}^{-1}$. The limiting molar conductivity of $Y^-$ ion, $\lambda^0_{Y^-}$ (in S cm$^2$mol$^{-1}$), is: [Given $\lambda^0_{X^+}=74.0\,\text{S cm}^2\text{mol}^{-1}$]

Select the reagents that reduce nitriles to primary amines. A. (i) \ce{LiAlH4}; (ii) \ce{H2O} B. \ce{Sn + HCl} C. \ce{H2/Ni} D. \ce{Na(Hg)/C2H5OH} E. \ce{Br2/aq.\ NaOH} Choose the correct answer from the options given below.

The following two reactions give the same foul-smelling product Z. $\ce{C2H5Cl ->[X] Z}$ $\ce{C2H5CONH2 ->[Br2 + NaOH] C2H5NH2 ->[CHCl3 / ethanolic KOH][\Delta] Z}$ X and Z, respectively, are:

The major product $Z$ formed in the following sequence of reactions is: \ce{C2H6 ->[Cl2/UV] X ->[NH3] Y ->[(i) NaNO2/HCl][(ii) H2O] Z}

Identify the reactions which give aniline as the major product. (A) $\ce{C6H5CN ->[LiAlH4]}$; (B) $\ce{C6H5CONH2 ->[KOH, Br2]}$; (C) $\ce{C6H5NO2 ->[NaBH4]}$; (D) $\ce{C6H5NHCOCH3 ->[HCl, H2O, \Delta]}$. Choose the correct answer: