Textbook Question
Which solid would you expect to have little or no band gap? a. Zn(s) b. Si(s) c. As(s)
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Ch.12 - Solids and Modern Material
Chapter 12, Problem 62
How many molecular orbitals are present in the valence band of a sodium crystal with a mass of 5.45 g?
Verified step by step guidance1
Determine the number of moles of sodium in the given mass using the formula: \( \text{moles} = \frac{\text{mass}}{\text{molar mass}} \). The molar mass of sodium (Na) is approximately 22.99 g/mol.
Calculate the number of sodium atoms using Avogadro's number (\(6.022 \times 10^{23}\) atoms/mol). Multiply the number of moles by Avogadro's number to find the total number of sodium atoms.
Understand that in a sodium crystal, each sodium atom contributes one valence electron to the formation of molecular orbitals in the valence band.
Recognize that the number of molecular orbitals in the valence band is equal to the number of valence electrons, which is the same as the number of sodium atoms in the crystal.
Conclude that the number of molecular orbitals in the valence band is equal to the number of sodium atoms calculated in step 2.
Related Practice
Textbook Question
Which solid would you expect to have the largest band gap? a. As(s) b. Sb(s) c. Bi(s)
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Textbook Question
How many molecular orbitals are present in the conduction band of a lithium crystal with a mass of 11.2 g?
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Textbook Question
A substance has a band gap of 6.9 eV at 273 K. Is this substance best classified as an insulator, a semiconductor, or a metal?
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Open Question
A substance has a band gap of 0.85 eV at 273 K. Is this substance best classified as an insulator, a semiconductor, or a metal?
Textbook Question
Indicate if each solid forms an n-type or a p-type semiconductor. a. germanium doped with gallium b. silicon doped with arsenic