List of top Chemistry Questions asked in JEE Main

$\text{2-chlorobutane} + \text{Cl}_2 \rightarrow \text{C}_4\text{H}_8\text{Cl}_2 \, (\text{isomers})$
$\text{Total number of optically active isomers shown by} \, \text{C}_4\text{H}_8\text{Cl}_2, \, \text{obtained in the above reaction is} \, \_\_\_\_\_\_.$

The incorrect statement regarding ethyne is

Number of metal ions characterized by flame test among the following is _______.
$\text{Sr}^{2+}, \text{Ba}^{2+}, \text{Ca}^{2+}, \text{Cu}^{2+}, \text{Zn}^{2+}, \text{Co}^{2+}, \text{Fe}^{2+}$

Major product of the following reaction is

Number of geometrical isomers possible for the given structure is/are ___________.

$\text{The pH of an aqueous solution containing 1 M benzoic acid (} pK_a = 4.20 \text{) and 1 M sodium benzoate is 4.5.}$
\(\text{The volume of benzoic acid solution in 300 mL of this buffer solution is \_\_\_\_\_\_ mL.}\)

The total number of correct statements, regarding the nucleic acids is_________.
A. RNA is regarded as the reserve of genetic information.
B. DNA molecule self-duplicates during cell division.
C. DNA synthesizes proteins in the cell.
D. The message for the synthesis of particular proteins is present in DNA.
E. Identical DNA strands are transferred to daughter cells.

$\text{Two reactions are given below:}$ \[ 2\text{Fe}_{(s)} + \frac{3}{2}\text{O}_{2(g)} \rightarrow \text{Fe}_2\text{O}_{3(s)}, \Delta H^\circ = -822 \, \text{kJ/mol} \] \[ \text{C}_{(s)} + \frac{1}{2}\text{O}_{2(g)} \rightarrow \text{CO}_{(g)}, \Delta H^\circ = -110 \, \text{kJ/mol} \] $\text{Then enthalpy change for the following reaction}$ \[ 3\text{C}_{(s)} + \text{Fe}_2\text{O}_{3(s)} \rightarrow 2\text{Fe}_{(s)} + 3\text{CO}_{(g)} \]

$\text{NO}_2 \text{ required for a reaction is produced by decomposition of } \text{N}_2\text{O}_5 \text{ in } \text{CCl}_4 \text{ as by equation}$
\[ 2\text{N}_2\text{O}_{5(g)} \rightarrow 4\text{NO}_{2(g)} + \text{O}_{2(g)} \]
$\text{The initial concentration of } \text{N}_2\text{O}_5 \text{ is } 3 \text{ mol L}^{-1} \text{ and it is } 2.75 \text{ mol L}^{-1} \text{ after 30 minutes.}$
$\text{The rate of formation of } \text{NO}_2 \text{ is } x \times 10^{-3} \text{ mol L}^{-1} \text{ min}^{-1} , \text{ value of } x \text{ is \_\_\_\_\_\_.}$

$\textbf{Number of complexes which show optical isomerism among the following is \_\_\_\_\_\_.}$
\[ \text{cis}-[\text{Cr(ox)}_2\text{Cl}_2]^{3-}, \quad [\text{Co(en)}_3]^{3+}, \] \[ \text{cis}-[\text{Pt(en)}_2\text{Cl}_2]^{2+}, \quad \text{cis}-[\text{Co(en)}_2\text{Cl}_2]^{+}, \] \[ \text{trans}-[\text{Pt(en)}_2\text{Cl}_2]^{2+}, \quad \text{trans}-[\text{Cr(ox)}_2\text{Cl}_2]^{3-} \]

$\textbf{Reduction potential of ions are given below:}$
\[ \begin{array}{ccc} \text{ClO}_4^- & \text{IO}_4^- & \text{BrO}_4^- \\ E^\circ = 1.19 \, \text{V} & E^\circ = 1.65 \, \text{V} & E^\circ = 1.74 \, \text{V} \\ \end{array} \]
The correct order of their oxidising power is:

The incorrect statement about Glucose is :

$\textbf{A and B formed in the following reactions are:}$ \[ \text{CrO}_2\text{Cl}_2 + 4\text{NaOH} \rightarrow \text{A} + 2\text{NaCl} + 2\text{H}_2\text{O} \] \[ \text{A} + 2\text{HCl} + 2\text{H}_2\text{O}_2 \rightarrow \text{B} + 3\text{H}_2\text{O} \]

The coordination environment of \( \text{Ca}^{2+} \) ion in its complex with \( \text{EDTA}^{4-} \) is:

The correct stability order of carbocations is

Match List I with List II

LIST-I	LIST-II
A. K2[Ni(CN)4]	I. sp3
B. [Ni(CO)4]	II. sp3d2
C. [Co(NH3)6]Cl3	III. dsp2
D. Na3[CoF6]	IV. d2sp3

Choose the correct answer from the options given below:

Match List I with List II

LIST-I (Cell)	LIST-II (Use/Property/Reaction)
A. Leclanche cell	IV. Reaction at anode Zn → Zn2+ + 2e-
B. Ni-Cd cell	III. Rechargeable
C. Fuel cell	I. Converts energy of combustion into electrical energy
D. Mercury cell	II. Does not involve any ion in solution and is used in hearing aids

Choose the correct answer from the options given below:

Statement I: Since fluorine is more electronegative than nitrogen, the net dipole moment of NF₃ is greater than NH₃.
Statement II: In NH₃, the orbital dipole due to the lone pair and the dipole moment of NH bonds are in opposite directions, but in NF₃, the orbital dipole due to the lone pair and the dipole moments of N-F bonds are in the same direction.
In light of the above statements, choose the most appropriate from the options given below:

The coordination geometry around the manganese in decacarbonyldimanganese(0) is

Statement I: Along the period, the chemical reactivity of the element gradually increases from group 1 to group 18.
Statement II: The nature of oxides formed by group 1 element is basic while that of group 17 elements is acidic.
In the light of the above statements, choose the most appropriate from the questions given below:

Match List I with List II

Choose the correct answer from the options given below:

If a substance ‘A’ dissolves in a solution of a mixture of ‘B’ and ‘C’ with their respective number of moles as \(n_a\), \(n_b\), and \(n_c\), the mole fraction of C in the solution is:

Alkaline oxidative fusion of \(MnO_2\) gives “A” which on electrolytic oxidation in alkaline solution produces B. A and B respectively are:

$\textbf{The orange colour of } \text{K}_2\text{Cr}_2\text{O}_7 \textbf{ and purple colour of KMnO}_4 \textbf{ is due to}$

Which of the following has a square pyramidal shape?