To solve for \( x + y \), where \( x \) and \( y \) are the number of electrons in the 4d orbitals of niobium (Nb) and ruthenium (Ru), respectively, we need to refer to the electron configurations of these elements:
Now, compute \( x + y \):
\( x + y = 4 + 7 = 11 \)
Check that the sum \( 11 \) falls within the specified range \([11, 11]\), confirming that our computed value is correct.
Therefore, the value of \( x + y \) is 11.
Energy of first Balmer line of H-atom is \( x \) kJ. The energy of the second Balmer line of H-atom is _____
In the given figure, the blocks $A$, $B$ and $C$ weigh $4\,\text{kg}$, $6\,\text{kg}$ and $8\,\text{kg}$ respectively. The coefficient of sliding friction between any two surfaces is $0.5$. The force $\vec{F}$ required to slide the block $C$ with constant speed is ___ N.
(Given: $g = 10\,\text{m s}^{-2}$) 
Method used for separation of mixture of products (B and C) obtained in the following reaction is: 