9. Quantum Mechanics

Consider the mass spectrum for a hypothetical element given below.
Which of the following statements correctly relates to this spectrum?

When an electron in a hydrogen atom moves from n = 8 to n = 2, light with what wavelength is emitted?

Which of the following transitions results in the emission of the highest-energy photon?

How many photons of light are emitted in a 4.50-mJ pulse of a laser with a wavelength of 555 nm?

When a copper salt such as Cu(NO3)2 is burned in a flame, a blue-green color is emitted. Which figure represents the emission spectrum for the element copper? (LO 5.6)? (a)

(b)

(c)

(d)

A certain quantum-mechanical system has the energy levels shown in the accompanying diagram. The energy levels are indexed by a single quantum number n that is an integer. (b) Which quantum numbers are involved in the transition that requires the least energy?

A certain quantum-mechanical system has the energy levels shown in the accompanying diagram. The energy levels are indexed by a single quantum number n that is an integer. (a) As drawn, which quantum numbers are involved in the transition that requires the most energy? (b) Which quantum numbers are involved in the transition that requires the least energy? (c) Based on the drawing, put the following in order of increasing wavelength of the light absorbed during the transition: (i) n = 1 to n = 2; (ii) n = 2 to n = 3; (iii) n = 2 to n = 4; (iv) n = 1 to n = 3.

The visible emission lines observed by Balmer all involved nf = 2. (a) Which of the following is the best explanation of why the lines with nf = 3 are not observed in the visible portion of the spectrum: (i) Transitions to nf = 3 are not allowed to happen, (ii) transitions to nf = 3 emit photons in the infrared portion of the spectrum, (iii) transitions to nf = 3 emit photons in the ultraviolet portion of the spectrum, or (iv) transitions to nf = 3 emit photons that are at exactly the same wavelengths as those to nf = 2.

The Lyman series of emission lines of the hydrogen atom are those for which nf = 1. (a) Determine the region of the electromagnetic spectrum in which the lines of the Lyman series are observed.

Spectroscopy is a technique that uses the interaction of radiant energy with matter to identify or quantify a substance in a sample. A deuterium lamp is often used a light source in the ultraviolet region of the spectrum and the emission spectrum is shown. Is this a continuous or line emission spectrum?

Sodium-vapor lamps are a common source of lighting. The emission spectrum from this type of lamp is shown. Is this a continuous or line emission spectrum?

According to the quantum-mechanical model for the hydrogen atom, which electron transition produces light with the longer wavelength: 3p¡2s or 4p¡3p ?

The series of emission lines of the hydrogen atom for which nf = 4 is called the Brackett series. (a) Determine the region of the electromagnetic spectrum in which the lines of the Brackett series are observed.