A Doubly-Ionized Lithium Atom $\mathrm { Li } ^ { + + }$

question 100

Multiple Choice

A doubly-ionized lithium atom $\mathrm { Li } ^ { + + }$ , which has 3 protons, undergoes a transition from the $n = 5$ state to the $n = 4$ state. What is the wavelength of the photon which is emitted during this
transition? $\left( c = 3.00 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } , 1 \mathrm { eV } = 1.60 \times 10 ^ { - 19 } \mathrm {~J} \right)$

• A) \(650 \mathrm {~nm}\)
• B) \(350 \mathrm {~nm}\)
• C) \(550 \mathrm {~nm}\)
• D) \(750 \mathrm {~nm}\)
• E) \(450 \mathrm {~nm}\)

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Definitions:

Circuit

A closed path through which electrical current flows or can flow.

Cathode

The electrode in a battery or electrochemical cell towards which positive ions move, typically where reduction reactions take place.

Diode

An electronic component that allows current to flow in one direction only, functioning as a one-way valve in electrical circuits.