Structure of Atom

In a multielectron atom, which of the following orbitals described by three quantum numbers will have same energy in absence of electric and magnetic fields? Choose the correct answer from the options given below:

1. B and C Only
2. C and D Only
3. A and B Only
4. D and E Only

Which of the following is/are not correct with respect to energy of atomic orbitals of hydrogen atom? Choose the correct answer from the options given below :

1. (A) and (B) only
2. (A) and (C) only
3. (B) and (D) only
4. (C) and (D) only

For hydrogen atom, the orbital/s with lowest energy is/are : Choose the correct answer from the options given below :

1. A only
2. B only
3. B, C and D only
4. A and E only

Heat treatment of muscular pain involves radiation of wavelength of about 900 nm. Which spectral line of H atom is suitable for this? Given : Rydberg constant RH = 105 cm-1, h = 6.6 10-34 J s, c = 3 108 m/s

1. Lyman series, 1
2. Balmer series, 2
3. Paschen series, 5 3
4. Paschen series, 3

Given below are two statements : In the light of the above statements, choose the correct answer from the options given below :

1. Both Statement I and Statement II are true
2. Both Statement I and Statement II are false
3. Statement I is false but Statement II is true
4. Statement I is true but Statement II is false

Given below are two statements about X-ray spectra of elements : In the light of the above statements, choose the correct answer from the options given below :

1. Statement I is false but Statement II is true
2. Both Statement I and Statement II are true
3. Statement I is true but Statement II is false
4. Both Statement I and Statement II are false

Radius of the first excited state of Helium ion is given as : a0 radius of first stationary state of hydrogen atom.

1. r = a04
2. r = 2a0
3. r = 4a0
4. r = a02

Given below are two statements : In the light of the above statements, choose the correct answer from the options given below :

1. Statement I is false but Statement II is true
2. Both Statement I and Statement II are false
3. Statement I is true but Statement II is false
4. Both Statement I and Statement II are true

Niobium (Nb) and ruthenium (Ru) have “x” and “y” number of electrons in their respective 4 d orbitals. The value of x+y is .