To determine the number of electrons present in all the completely filled subshells with principal quantum number n=4 and spin quantum number s=+½, we first identify the available subshells for n=4. These are 4s, 4p, 4d, and 4f.
Each subshell can hold a specific number of electrons:
Next, since we are only interested in electrons with s=+½, we consider half of those in each subshell:
| Subshell | Total Electrons | Electrons with s=+½ |
|---|---|---|
| 4s | 2 | 1 |
| 4p | 6 | 3 |
| 4d | 10 | 5 |
| 4f | 14 | 7 |
Summing these, the total number of electrons with s=+½ is 1+3+5+7=16.
This value fits the expected range of 16,16, confirming its correctness. Therefore, the number of electrons in all completely filled subshells with n=4 and s=+½ is 16.
For n = 4, the possible subshells and their electron capacities are:
So, the total number of electrons is 16.
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
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 : \(A_2 \rightleftharpoons 2A\)
A black body is at a temperature of 2880 K. The energy of radiation emitted by this body with wavelength between 499 nm and 500 nm is U1, between 999 nm and 1000 nm is U2 and between 1499 nm and 1500 nm is U3. The Wien's constant, b = 2.88×106 nm-K. Then,