$Nd ^{2+}=$ ___________
Nd(60)=[Xe]4f45d06s2
Nd2+=[Xe]4f45d05s0
So, the correct option is (D): 4f4
\[ \text{Nd(60)} = [\text{Xe}] 4f^4 5d^0 6s^2 \]
For \( \text{Nd}^{2+} \), two electrons are removed (typically from the 6s orbital first):\[ \text{Nd}^{2+} = [\text{Xe}] 4f^4 5d^0 5s^0 \]
Thus, the correct answer is \( 4f^4 \).What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)

Cobalt chloride when dissolved in water forms pink colored complex $X$ which has octahedral geometry. This solution on treating with cone $HCl$ forms deep blue complex, $\underline{Y}$ which has a $\underline{Z}$ geometry $X, Y$ and $Z$, respectively, are
Given below are two statements:
Statement I: D-(+)-glucose + D-(+)-fructose $\xrightarrow{H_2O}$ sucrose sucrose $\xrightarrow{\text{Hydrolysis}}$ D-(+)-glucose + D-(+)-fructose
Statement II: Invert sugar is formed during sucrose hydrolysis.
In the light of the above statements, choose the correct answer from the options given below -
Match items of column I and II
| Column I (Mixture of compounds) | Column II (Separation Technique) | ||
| A | H2O/CH2Cl2 | i | Crystallization |
| B | ![]() | ii | Differential solvent extraction |
| C | Kerosene/Naphthalene | iii | Column chromatography |
| D | C6H12O6/NaCl | iv | Fractional Distillation |
| List I (Mixture) | List II (Separation Technique) | ||
| A | CHCl3+C6H5NH2 | i | Steam distillation |
| B | C6H14+C5H12 | ii | Differential extraction |
| C | C6H5NH2+H2O | iii | Distillation |
| D | Organic compound in H2O | iv | Fractional distillation |
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)
The scientific study of matter’s properties and behaviour is known as chemistry. It is a natural science that studies the elements that makeup matter, as well as the compounds, made up of atoms, molecules, and ions: their composition, structure, qualities, and behaviour, as well as the changes that occur when they mix with other things.