Free-Electron Theory of Metals: the Fermi Level (Energy) of a Metal

question 15

Multiple Choice

Free-electron theory of metals: The Fermi level (energy) of a metal is 5.5 eV. What is the number of conduction electrons per unit volume for this metal? (m_el = 9.11 × 10^-31 kg, 1 eV = 1.60 × 10^-19 J, h = 6.626 × 10^-34 J ∙ s)

• A) 5.8 × 10²⁸ / m³
• B) 6.2 × 10²⁸ / m³
• C) 4.1 × 10²⁸ / m³
• D) 8.4 × 10²⁸ / m³
• E) 3.3 × 10²⁸ / m³

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Definitions:

Dorsal Hollow Nerve Cord

A distinctive feature of chordates, this is a nerve cord found along the back or dorsal side of the organism.

Notochord

A flexible rod made out of a material similar to cartilage that provides support in the embryonic stages of all chordates, including humans.

Vertebral Column

Portion of the vertebrate endoskeleton that houses the spinal cord; consists of many vertebrae separated by intervertebral discs.

Dorsal Notochord

A flexible rod-shaped structure in the embryo of all chordates, including humans, that provides skeletal support and defines the primitive axis of the embryo.