Line Spectra and Electronic Configuration (Qn from Kognity)

Which statement(s) is/are correct for the emission line spectrum of the hydrogen atom?

I. The lines converge at lower energies

II. Electron transitions to n = 1 are responsible for lines in the UV region

III. Lines are produced when electrons transition from higher to lower energy levels

• II and III only

• I and III only

• I and II only

• I, II and III

An emission line spectrum consists of a series of coloured lines that converge at high frequencies. These emission spectra provide evidence for which of the following?

• Electrons transition from higher to lower energy levels with the higher energy levels being closer together

• Electrons transition from lower to higher energy levels with the lower energy levels being closer together

• Electrons transition from higher to lower energy levels with the lower energy levels being closer together

• Electrons transition from lower to higher energy levels with the higher energy levels being closer together

Which statement is correct for the emission spectrum of the hydrogen atom?

• The lines corresponding to the greatest emission of energy are in the ultraviolet region

• The lines converge at lower energies

• The lines are produced when electrons transition from lower to higher energy levels

• The lines in the visible region involve electron transitions into the energy level closest to the nucleus

Determine what information about the structure of a helium atom can be gained from its emission spectrum.

• Most of the mass of the atom is in its nucleus

• A helium atom contains two electrons and two protons

• The electrons in the helium atom are located close to the nucleus

• The electrons exist in energy levels

Deduce which of the following the emission line spectrum of an element can be used for.

• To identify an unknown element 

• To determine the number of neutrons in the nucleus of an atom

• To determine the number of electrons in an atom

• To determine the relative atomic mass of a compound

Determine the total number of electrons in the d orbitals of an atom of tin, Sn (Z = 50). 

(a)  

Deduce which of the following ground-state electron configurations contain unpaired electrons.

I. [He] 2s² 2p² 

II. [He] 2s² 2p³

III. [He] 2s² 2p⁴

• I, II and III

• I only

• I and II only

• II and III only

Which of the following elements has atoms with only two half-filled atomic orbitals in the ground state?

• Phosphorus

• Beryllium

• Nitrogen 

• Carbon

Which of the following statements is correct concerning atomic orbitals and energy levels in the electron configurations of the known elements?

• The maximum number of electrons in a single d orbital is 10

• The maximum number of electrons in the 4^th main energy level is 18

• Yttrium, Y, (Z = 39) is the first element in the Periodic Table with an electron in an f orbital

• Within main energy levels 4 and 5, the sub-level with the highest energy is labelled f

Hund's rule states which of the following?

• Electrons occupy degenerate (same energy) atomic orbitals singly with the same spin before doubly occupying each orbital

• Electrons occupy atomic orbitals of different energies singly with the same spin before doubly occupying each orbital

• Electrons occupy degenerate (same energy) atomic orbitals singly with opposite spins before doubly occupying each orbital

• Electrons doubly occupy atomic orbitals of different energies with the same spin