Chemistry presentation
An Introduction to
Structure and Types of
Solids
Categories
Crystalline Solids
• Highly regular arrangement of atoms, ions and molecule • The position of the components are represent by a lattice • It has smallest repeating unit of lattice is called unit cell
• Such as diamond, salt, sugar
Amorphous Solid
• A noncrystalline solid which their components not organized in lattice pattern.
• Such as glass, plastic, gel
Question
1. X rays from a copper X-ray tube (λ = 154) were diffracted at an angle of 14.22 degrees by a crystal of silicon. Assuming firstorder diffraction (n= 1 in the Bragg equation), What is the interlunar spacing of silicon? nλ = 2d sin θ
1(154) = 2d sin 14.22
154 = 2d (0.245)
2d = 626.92 d = 313.46
2. A topaz crystal has an interplanar spacing (d) of 1.36 Å (1 Å =
). Calculate the wavelength of the X ray that should be used if θ = 15.0° (assume n = 1) nλ = 2d sin θ
1(λ) = 2(1.36) sin 15 λ = 2(1.36)(0.258) λ = 0.704
Structure and Types of
Solids
Categories
Crystalline Solids
• Highly regular arrangement of atoms, ions and molecule • The position of the components are represent by a lattice • It has smallest repeating unit of lattice is called unit cell
• Such as diamond, salt, sugar
Amorphous Solid
• A noncrystalline solid which their components not organized in lattice pattern.
• Such as glass, plastic, gel
Question
1. X rays from a copper X-ray tube (λ = 154) were diffracted at an angle of 14.22 degrees by a crystal of silicon. Assuming firstorder diffraction (n= 1 in the Bragg equation), What is the interlunar spacing of silicon? nλ = 2d sin θ
1(154) = 2d sin 14.22
154 = 2d (0.245)
2d = 626.92 d = 313.46
2. A topaz crystal has an interplanar spacing (d) of 1.36 Å (1 Å =
). Calculate the wavelength of the X ray that should be used if θ = 15.0° (assume n = 1) nλ = 2d sin θ
1(λ) = 2(1.36) sin 15 λ = 2(1.36)(0.258) λ = 0.704