Which of the following statements on quantum numbers is not correct?
A. Quantum numbers, n,1, m and ms are needed to describe an electron in an atom completely
B. Quantum numbers n, l, m and s are obtained by solving the Schrodinger wave equation.
C. A subshell in an atom can be designated with two quantum numbers n and 1
D. The maximum value of 1 is equal to n -1 and that of m is + l

Hint: Quantum numbers come in four different types. The values of the various quantum numbers fall into different bands. We shall investigate this range, or the permitted values of the quantum numbers, and then provide a solution.

Complete answer:
A Schrodinger equation is written in the form of:
${\nabla ^2}\Psi + \dfrac{{8{\pi ^2}m}}{{{h^2}}}(E - V)\Psi = 0$

Where $\Psi $ is amplitude of wave, E is total energy of an electron, V is potential energy, m is mass of electron and h is Planck’s constant.

After solving the equation, we get the set of quantum numbers. These quantum numbers tell us about the energies of electrons in atoms. They also give information about orientation and shape of electrons around the nucleus. The Schrodinger equation gives the principal quantum number, Azimuthal quantum number and magnetic quantum number. But spin quantum numbers are not exactly like the Schrodinger equation. Spin quantum number is related to the electron’s spin in doublets of the orbital.

Therefore, the quantum number which we do not get from the Schrodinger equation is spin quantum number. Hence, option B is the correct answer.


Note: Principal quantum number (n) tells about the principal shell of the electron. If n=2, that means electrons are present in the second principal shell. The angular quantum number (l) tells us about the shape of an orbital in which electrons are present. Magnetic quantum numbers tell the orientation and number of orbitals. Spin quantum number (s) help to know about the direction of spin of electrons. The spin of an electron can be represented by only two quantities either $\dfrac{1}{2}$or$ - \dfrac{1}{2}$.