Question:
The correct set of four quantum numbers for outermost electron of potassium ($Z=19$) is
The correct set of four quantum numbers for outermost electron of potassium ($Z=19$) is
Show Hint
$s$-orbital $\rightarrow l=0, m=0$. Outermost shell for $K$ is $n=4$.
Updated On: Apr 10, 2026
- $4, 0, 0, \frac{1}{2}$
- $3, 1, 0, \frac{1}{2}$
- $4, 0, 0, \frac{1}{2}$
- $3, 0, 0, \frac{1}{2}$
Show Solution
Verified By Collegedunia
The Correct Option is C
Solution and Explanation
Step 1: Configuration
Potassium ($Z=19$): $1s^{2}, 2s^{2}, 2p^{6}, 3s^{2}, 3p^{6}, 4s^{1}$.
Step 2: Valence Electron
The outermost (valence) electron is in the $4s$ orbital ($4s^{1}$).
Step 3: Quantum Numbers
- Principal ($n$) = 4
- Azimuthal ($l$) for $s$-orbital = 0
- Magnetic ($m_{l}$) = 0
- Spin ($s$) = $+1/2$ or $-1/2$.
Step 4: Conclusion
The correct set is $4, 0, 0, 1/2$.
Final Answer: (c)
Potassium ($Z=19$): $1s^{2}, 2s^{2}, 2p^{6}, 3s^{2}, 3p^{6}, 4s^{1}$.
Step 2: Valence Electron
The outermost (valence) electron is in the $4s$ orbital ($4s^{1}$).
Step 3: Quantum Numbers
- Principal ($n$) = 4
- Azimuthal ($l$) for $s$-orbital = 0
- Magnetic ($m_{l}$) = 0
- Spin ($s$) = $+1/2$ or $-1/2$.
Step 4: Conclusion
The correct set is $4, 0, 0, 1/2$.
Final Answer: (c)
Was this answer helpful?
0
0
Top MET Physics Questions
- A coil of 100 turns and area $2 \times 10^{-2}m^2 $ is pivoted about a vertical diameter in a uniform magnetic field and carries a current of 5A. When the coil is held with its plane in north-south direction, it experiences a couple of 0.33 Nm. When the plane is east-west, the corresponding couple is 0.4 Nm, the value of magnetic induction is [Neglect earth's magnetic field]
- Radiation, with wavelength 6561 $?$ falls on a metal surface to produce photoelectrons. The electrons are made to enter a uniform magnetic field of $3 \times 10^{-4} T$. If the radius of the largest circular path followed by the electrons is 10 mm, the work function of the metal is close to :
- In intrinsic semiconductor at room temperature number of electrons and holes are
- A rope of mass $0.1\, kg$ is connected at the same height of two opposite walls. It is allowed to hang under its own weight. At [he contact point between the rope and the wall, the rope makes an angle $ \theta =10^{\circ} $ with respect to horizontal. The tension in the rope at its midpoint between the walls is
- At great distances from an electric dipole, the electric field strength due to the dipole varies with the distance as
View More Questions
Top MET Kirchhoff's Laws Questions
- A closed mesh has a potential \( V' \), current \( I \), and resistance \( R \). If \( V' = 0.5 \,\text{V} \), \( I = 0.1 \,\text{A} \), and \( R = 20 \,\Omega \), the total voltage \( V \) is:
- The resistance of an ideal ammeter is:
- For the reaction $H_2O (l) \rightleftharpoons H_2O(g)$ at 373 K and 1 atm pressure
- An electric kettle has two coils. When one coil is switched on, it takes 10 min to boil water and when the second coil is switched on it takes 20 min to boil same amount of water. The time taken when both coils are used in parallel is \(n\) seconds. Find \(n\).
- The resistance of a wire at \(20^\circ C\) is \(20\Omega\) and at \(500^\circ C\) is \(60\Omega\). At which temperature its resistance will be \(25\Omega\)?
View More Questions
Top MET Questions
- A coil of 100 turns and area $2 \times 10^{-2}m^2 $ is pivoted about a vertical diameter in a uniform magnetic field and carries a current of 5A. When the coil is held with its plane in north-south direction, it experiences a couple of 0.33 Nm. When the plane is east-west, the corresponding couple is 0.4 Nm, the value of magnetic induction is [Neglect earth's magnetic field]
- $\int\limits_{0}^{8}| x -5| d x$ is equal to
- Radiation, with wavelength 6561 $?$ falls on a metal surface to produce photoelectrons. The electrons are made to enter a uniform magnetic field of $3 \times 10^{-4} T$. If the radius of the largest circular path followed by the electrons is 10 mm, the work function of the metal is close to :
- In intrinsic semiconductor at room temperature number of electrons and holes are
- Which of the following product is formed in the reaction $ CH_3MgBr {->[(i)CO_2][(ii)H_2O]} ? $
View More Questions