Electronic configuration

The 2s and the 2p orbital energies of hydrogen atom are $E_{2s}(\mathrm H)$ and $E_{2p}(\mathrm H)$, respectively. The 2s and the 2p orbital energies of lithium atom are $E_{2s}(\mathrm{Li})$ and $E_{2p}(\mathrm{Li})$, respectively. The correct option(s) about the orbital energies is(are)

Which of the following is correct set of 4 quantum numbers of 19th electron in Chromium (Atomic number = 24) in accordance with Aufbau principle?

A monoatomic anion ($\ce{A-}$) has 45 neutrons and 36 electrons. Atomic mass, group in the periodic table and physical state at room temperature of the element (A) respectively are

Pairs of elements with the same number of electrons in their respective 4f orbital are

[Atomic number. Eu-63, Gd-64, Dy-66, Ho-67, Tm-69, Yb-70, Lu-71, Hf-72]

A. (Eu and Gd)

B. (Dy and Ho)

C. (Yb and Hf)

D. (Lu and Tm)

Choose the correct answer from the options given below:

Arrange the following atomic orbitals of multi electron atoms in order of increasing energy.

A. $n=3$, $l=2$, $m=+1$

B. $n=4$, $l=0$, $m=0$

C. $n=6$, $l=1$, $m=0$

D. $n=5$, $l=1$, $m=+1$

E. $n=2$, $l=1$, $m=+1$

Choose the correct answer from the options given below:

Identify the correct statements from the following :

A. Heisenberg uncertainty principle is applicable to electrons.

B. The size of $2p_x$ orbital is less than the size of $3p_x$ orbital.

C. The energy of 2s orbital of H atom is equal to the energy of 2s orbital of Li.

D. The electronic configuration of Cr is $[\mathrm{Ar}]\,3d^54s^1$

Choose the correct answer from the options given below:

The pair, in which ions are isoelectronic with $\mathrm{Al^{3+}}$ is :

The metal ion (in gaseous state) with lowest spin-only magnetic moment value is

The 'f' orbitals are half and completely filled, respectively in lanthanide ions

[Given : Atomic no. Eu, 63; Sm, 62; Tm, 69; Tb, 65; Yb, 70; Dy, 66]

Element "E" belongs to the period 4 and group 16 of the periodic table. The valence shell electron configuration of the element, which is just above "E" in the group is

Which of the following statements are correct ?

(A) The electronic configuration of Cr is [Ar] 3d$^5$ 4s$^1$.

(B) The magnetic quantum number may have a negative value.

(C) In the ground state of an atom, the orbitals are filled in order of their increasing energies.

(D) The total number of nodes are given by $n-2$.

Choose the most appropriate answer from the options given below :

The electronic configuration of Pt (atomic number 78) is :

Consider an imaginary ion ${}^{48}_{22}\mathrm X^{3-}$. The nucleus contains 'a'% more neutrons than the number of electrons in the ion. The value of 'a' is ______. [nearest integer]

The correct decreasing order of energy for the orbitals having, following set of quantum numbers :

(A) n = 3, l = 0, m = 0
(B) n = 4, l = 0, m = 0
(C) n = 3, l = 1, m = 0
(D) n = 3, l = 2, m = 1

is :

Given below are the quantum numbers for 4 electrons.

A. n = 3, l = 2, m$_l$ = 1, m$_s$ = +1/2
B. n = 4, l = 1, m$_l$ = 0, m$_s$ = +1/2
C. n = 4, l = 2, m$_l$ = −2, m$_s$ = −1/2
D. n = 3, l = 1, m$_l$ = −1, m$_s$ = +1/2

The correct order of increasing energy is

Aqueous solution of which salt will not contain ions with the electronic configuration $1s^22s^22p^63s^23p^6$ ?

If the principal quantum number n = 6, the correct sequence of filling of electrons will be :

The correct set of four quantum numbers for the valence electrons of rubidium atom ($Z=37$) is :

Given that the abundances of isotopes $^{54}$Fe, $^{56}$Fe and $^{57}$Fe are 5%, 90% and 5%, respectively, the atomic mass of Fe is