JEE Mains · Chemistry · STD 12 - 4. d and f- block elements
The calculated spin-only magnetic moments of \(\mathrm{K}_3\left[\mathrm{Fe}(\mathrm{OH})_6\right]\) and \(\mathrm{K}_4\left[\mathrm{Fe}(\mathrm{OH})_6\right]\) respectively are _______.
- A 3.87 and 4.90 B.M.
- B 4.90 and 5.92 B.M.
- C 4.90 and 4.90 B.M.
- D 5.92 and 4.90 B.M.
Answer & Solution
Correct Answer
(D) 5.92 and 4.90 B.M.
Step-by-step Solution
Detailed explanation
\(\begin{aligned} & \mathrm{K}_3\left[\mathrm{Fe}(\mathrm{OH})_6\right] \\ & \mathrm{Fe}^{3+} \Rightarrow 3 \mathrm{~d}^5 \\ & \mathrm{Fe}^{3+} \text { with } \mathrm{OH}^{-}(\mathrm{WFL}) \\ & =\mathrm{t}_{29}{ }^3 \mathrm{e}_{\mathrm{g}}{ }^2 \end{aligned}\) Number of unpaired…
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Chemistry
- Given below are two statements: Statement\(-I\) \(: \alpha\) and \(\beta\) forms of sulphur can change reversibly between themselves with slow heating or slow cooling. Statement\(-II :\) At room temperature the stable crystalline form of sulphur is monoclinic sulphur. In the light of the above statements, choose the correct answer from the options given below:JEE Mains 2021 Easy
- In which of the following order the given complex ions are arranged correctly with respect to their decreasing spin only magnetic moment? \((i)\) \(\left[ FeF _{6}\right]^{3-}\) \((ii)\) \(\left[ Co \left( NH _{3}\right)_{6}\right]^{3+}\) \((iii)\) \(\left[ NiCl _{4}\right]^{2-}\) \((iv)\) \(\left[ Cu \left( NH _{3}\right)_{4}\right]^{2+}\)JEE Mains 2021 Hard
- Find the compound ' A ' from the following reaction sequences.
\(\mathrm{A} \xrightarrow{\text { aqua-regia }} \mathrm{B} \xrightarrow[\text { (2) } \mathrm{AcOH}]{\text { (1) } \mathrm{KNO}_2 \mid \mathrm{NH}_4 \mathrm{OH}} \text { yellow ppt }\)JEE Mains 2025 Hard - Given below are two statements:
Statement I: Aluminium is more electropositive than thallium as the standard electrode potential value of \(E^{\circ}_{\text{Al}^{3+}/\text{Al}}\) is negative and \(E^{\circ}_{\text{Tl}^{3+}/\text{Tl}}\) is positive.
Statement II: The sum of first three ionization enthalpies of boron is very high when compared to that of aluminium. Due to this reason boron forms covalent compounds only and aluminium forms \(\text{Al}^{3+}\) ion.
In the light of the above statements, choose the correct answer from the options given belowJEE Mains 2026 Medium - The rate constant \((k)\) of a reaction is measured at different temperatures \((T),\) and the data are plotted in the given figure. The activation energy of the reaction in \(kJ\, mol ^{-1}\) is : (\(R\) is gas constant)
JEE Mains 2020 Medium - Given below are two statements: Statement \((I)\) : \(A\) Buffer solution is the mixture of a salt and an acid or a base mixed in any particular quantities. Statement \((II)\) : Blood is naturally occurring buffer solution whose \(\mathrm{pH}\) is maintained by \(\mathrm{H}_2 \mathrm{CO}_3 / \mathrm{HCO}_3\) concentrations. In the light of the above statements, choose the correct answer from the options given below.JEE Mains 2024 Medium
More PYQs from JEE Mains
- In a Young's double slit experiment, \(16\) fringes are observed in a certain segment of the screen when light of wavelength \(700 \,nm\) is used. If the wavelength of light is changed to \(400 \,nm\), the number of fringes observed in the same segment of the screen would be........JEE Mains 2020 Medium
- The correct order of the first ionization enthalpy is _______.JEE Mains 2024 Medium
- Given below are two statements: Statement \(I :\) Bohr's theory accounts for the stability and line spectrum of \(Li ^{+}\) ion. Statement \(II :\) Bohr's theory was unable to explain the splitting of spectral lines in the presence of a magnetic field. In the light of the above statements, choose the most appropriate answer from the options given below:JEE Mains 2021 Medium
- Arrange the following coordination compounds in the increasing order of magnetic moments. (Atomic numbers: \(Mn =25 ; Fe =26\) ) \((A)\) \(\left[ FeF _{6}\right]^{3-}\) \((B)\) \(\left[ Fe ( CN )_{6}\right]^{3-}\) \((C)\) \(\left[ MnCl _{6}\right]^{3-}\) (high spin) \((D)\) \(\left[ Mn ( CN )_{6}\right]^{3-}\)JEE Mains 2022 Medium
- Three moles of \(\mathrm{AgCl}\) get precipitated when one mole of an octahedral co-ordination compound with empirical formula \(\mathrm{CrCl}_{3} \cdot 3 \mathrm{NH}_{3} \cdot 3 \mathrm{H}_{2} \mathrm{O}\) reacts with excess of silver nitrate. The number of chloride ions satisfying the secondary valency of the metal ion is \(......\)JEE Mains 2021 Hard
- Diameter of a plano-convex lens is \(6 \,cm\) and thickness at the centre is \(3\, mm\). If the speed of light in the material of the lens is \(2 \times 10^8 m/sec\), the focal length of the lens is.......\(cm\)JEE Mains 2021 Hard