JEE Mains JEE Advance BITSAT
JEE Mains | PYQ

Year

All years 2026 2025 2024 2023 2022 2021

The correct order of basicity of oxides of vanadium is:

The total change in the oxidation state of manganese involved in the reaction of \( \text{KMnO}_4 \) and potassium iodide in the acidic medium is __________.

Which halogen is known to cause the reaction given below:
\( 2\mathrm{Cu^{2+}} + 4\mathrm{X^-} \rightarrow \mathrm{Cu_2X_2} \, \mathrm{(s)} + \mathrm{X_2} \)

\( \mathrm{KMnO_4} \) oxidises \( \mathrm{I^-} \) in acidic and neutral/faintly alkaline solution, respectively, to:

In alkaline medium, the reduction of permanganate anion involves a gain of _______ electrons.

Which of the following elements have half-filled f-orbitals in their ground state? (Given: atomic number \( \mathrm{Sm} = 62 \); \( \mathrm{Eu} = 63 \); \( \mathrm{Tb} = 65 \); \( \mathrm{Gd} = 64 \), \( \mathrm{Pm} = 61 \))
A. \( \mathrm{Sm} \) B. \( \mathrm{Eu} \) C. \( \mathrm{Tb} \) D. \( \mathrm{Gd} \) E. \( \mathrm{Pm} \)

Given below are two statements:
Statement I: Aqueous solution of \( \mathrm{K}_2\mathrm{Cr}_2\mathrm{O}_7 \) is preferred as a primary standard in volumetric analysis over \( \mathrm{Na}_2\mathrm{Cr}_2\mathrm{O}_7 \) aqueous solution.
Statement II: \( \mathrm{K}_2\mathrm{Cr}_2\mathrm{O}_7 \) has a higher solubility in water than \( \mathrm{Na}_2\mathrm{Cr}_2\mathrm{O}_7 \).
In the light of the above statements, choose the correct answer from the options given below:

Strong reducing and oxidizing agents among the following, respectively, are:

Which one amongst the following are good oxidizing agents?
(A) \( \mathrm{Sm^{2+}} \) (B) \( \mathrm{Ce^{2+}} \) (C) \( \mathrm{Ce^{4+}} \) (D) \( \mathrm{Tb^{4+}} \)
Choose the most appropriate answer from the options given below:

The magnetic moment of a transition metal compound has been calculated to be \( 2.87 \) B.M. The metal ion is:

Cobalt chloride when dissolved in water forms pink colored complex $\underline{\text{X}}$ which has octahedral geometry.

This solution on treating with conc $\text{HCl}$ forms deep blue complex, $\underline{\text{Y}}$ which has a $\underline{\text{Z}}$ geometry. $\text{X}$, $\text{Y}$ and $\text{Z}$, respectively are:

In chromyl chloride the number of d-electrons present on chromium is same as in:
(Given atomic number of Ti : \( 22 \), V : \( 23 \), Cr : \( 24 \), Mn : \( 25 \), Fe : \( 26 \))

\( \mathrm{Nd}^{2+} = \_\_\_\_\_ \)

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R)
Assertion (A): The first ionization enthalpy of \( 3d \) series elements is more than that of group \( 2 \) metals
Reason (R): In \( 3d \) series of elements successive filling of d-orbitals takes place.
In the light of the above statements, choose the correct answer from the options given below:

When \( \mathrm{Cu^{2+}} \) ion is treated with \( \mathrm{KI} \), a white precipitate, \( X \) appears in solution. The solution is titrated with sodium thiosulphate, the compound \( Y \) is formed, \( X \) and \( Y \) respectively are:

Prolonged heating is avoided during the preparation of ferrous ammonium sulphate to:

Formulae for Nessler’s reagent is:

The set of correct statements is:
(i) Manganese exhibits \( +7 \) oxidation state in its oxide.
(ii) Ruthenium and Osmium exhibit \( +8 \) oxidation in their oxides.
(iii) Sc shows \( +4 \) oxidation state which is oxidizing in nature.
(iv) Cr shows oxidizing nature in \( +6 \) oxidation state.

How many of the following metal ions have similar value of spin only magnetic moment in gaseous state _________ ? (Given: Atomic number: V, \(23\); Cr, \(24\); Fe, \(26\); Ni, \(28\))
\( \mathrm{V^{3+}}, \mathrm{Cr^{3+}}, \mathrm{Fe^{2+}}, \mathrm{Ni^{3+}} \)

Which of the following statements are correct?
(A) The \( \mathrm{M}^{3+} / \mathrm{M}^{2+} \) reduction potential for iron is greater than manganese.
(B) The higher oxidation states of first row d-block elements get stabilized by oxide ion
(C) Aqueous solution of \( \mathrm{Cr}^{2+} \) can liberate hydrogen from dilute acid
(D) Magnetic moment of \( \mathrm{V}^{2+} \) is observed between \( 4.4 - 5.2 \) \( \mathrm{BM} \)
Choose the correct answer from the options given below:

Highest oxidation state of Mn is exhibited in \( \mathrm{Mn_2O_7} \). The correct statements about \( \mathrm{Mn_2O_7} \) are
(A) Mn is tetrahedrally surrounded by oxygen atoms
(B) Mn is octahedrally surrounded by oxygen atoms
(C) Contains Mn-O-Mn bridge
(D) Contains Mn-Mn bond
Choose the correct answer from the option given below:

The pair of lanthanides in which both elements have high third-ionization energy is:

← PreviousQuestion 13 of 22Next →

JEE Main 2023 31st Jan Morning Shift

\( \mathrm{Nd}^{2+} = \_\_\_\_\_ \)