Consider the following test for a group-IV cation. \[ \text{M}^{2+} + \text{H}_2\text{S} \rightarrow \text{A (Black precipitate)} + \text{byproduct} \] \[ \text{A + aqua regia} \rightarrow \text{B + NOCl + S + H}_2\text{O} \] \[ \text{B + KNO}_2 + \text{CH}_3\text{COOH} \rightarrow \text{C + byproduct} \] The spin-only magnetic moment value of the metal complex \( \text{C} \) is \( \dots \dots \dots \) BM. (Nearest integer)
Correct Answer: 0
Solution and Explanation
From the reactions, the metal complex formed is likely in the 4$^+$ oxidation state, which leads to no unpaired electrons. For such complexes, the spin-only magnetic moment is zero because all electrons are paired. Hence, the magnetic moment is:
\( \mu = 0 { BM}\)
Thus, the correct answer is (0).
Top Questions on Qualitative Analysis
Match List I with List II:
Choose the correct answer from the options given below:- NEET (UG) - 2025
- Chemistry
- Qualitative Analysis
Among the following cations, the number of cations which will give characteristic precipitate in their identification tests with
\(K_4\)[Fe(CN)\(_6\)] is : \[ {Cu}^{2+}, \, {Fe}^{3+}, \, {Ba}^{2+}, \, {Ca}^{2+}, \, {NH}_4^+, \, {Mg}^{2+}, \, {Zn}^{2+} \]- JEE Main - 2025
- Chemistry
- Qualitative Analysis
- Given below are two statements:
Statement I: In Lassaigne's test, the covalent organic molecules are transformed into ionic compounds.
Statement II: The sodium fusion extract of an organic compound having N and S gives prussian blue colour with FeSO4 and Na4[Fe(CN)6].
In the light of the above statements, choose the correct answer from the options given below.- JEE Main - 2025
- Chemistry
- Qualitative Analysis
- For a double-strand DNA, one strand is given below: The amount of energy required to split the double-strand DNA into two single strands is . kcal mol........\(^{-1}\). [Given: Average energy per H-bond for A-T base pair = 1 kcal mol\(^{-1}\), G-C base pair = 1.5 kcal mol\(^{-1}\), and A-U base pair = 1.25 kcal mol\(^{-1}\). Ignore electrostatic repulsion between the phosphate groups]
- JEE Advanced - 2024
- Chemistry
- Qualitative Analysis
- A sample initially contains only U-238 isotope of uranium. With time, some of the U-238 radioactively decays into Pb-206 while the rest remains undisintegrated. When the age of the sample is \( P \times 10^8 \) years, the ratio of the mass of Pb-206 to that of U-238 in the sample is found to be 7. The value of \( P \) is: \[ \text{[Given: Half-life of U-238 = \(4.5 \times 10^9\) years; \(\log_e2 = 0.693\)]} \]
- JEE Advanced - 2024
- Chemistry
- Qualitative Analysis
Questions Asked in JEE Main exam
If the system of equations \[ x + 2y - 3z = 2, \quad 2x + \lambda y + 5z = 5, \quad 14x + 3y + \mu z = 33 \] has infinitely many solutions, then \( \lambda + \mu \) is equal to:}
- JEE Main - 2025
- Calculus
- An electric dipole of mass \( m \), charge \( q \), and length \( l \) is placed in a uniform electric field \( E = E_0 \hat{i} \). When the dipole is rotated slightly from its equilibrium position and released, the time period of its oscillations will be:
- JEE Main - 2025
- Electric Dipole
The equilibrium constant for decomposition of $ H_2O $ (g) $ H_2O(g) \rightleftharpoons H_2(g) + \frac{1}{2} O_2(g) \quad (\Delta G^\circ = 92.34 \, \text{kJ mol}^{-1}) $ is $ 8.0 \times 10^{-3} $ at 2300 K and total pressure at equilibrium is 1 bar. Under this condition, the degree of dissociation ($ \alpha $) of water is _____ $\times 10^{-2}$ (nearest integer value). [Assume $ \alpha $ is negligible with respect to 1]
- JEE Main - 2025
- Law Of Chemical Equilibrium And Equilibrium Constant
- The distance of the point \( P(1, 2, 3) \) from the plane \( 3x - 4y + 12z - 7 = 0 \) is:
- JEE Main - 2025
- Geometry and Vectors
- Two iron solid discs of negligible thickness have radii \( R_1 \) and \( R_2 \) and moment of inertia \( I_1 \) and \( I_2 \), respectively. For \( R_2 = 2R_1 \), the ratio of \( I_1 \) and \( I_2 \) would be \( \frac{1}{x} \), where \( x \) is:
- JEE Main - 2025
- System of Particles & Rotational Motion