What is materials science? - ANSWER The investigation of the
relationship between the structures and properties of materials
What are three classifications of materials? - ANSWER Metals,
ceramics, and polymers
What are metals? - ANSWER Non-localized electrons and good
conductors of electricity and heat; strong; deformable
What are ceramics? - ANSWER Examples: clay, cement, and glass.
Insulative to the flow of electricity and heat; resistant to high
temperatures and harsh environments; hard; brittle
What are polymers? - ANSWER Organic components comprised of
carbon, hydrogen, and other non-metals
What makes up an atomic number (Z)? - ANSWER The number of
protons in the nucleus
What makes up an atomic mass (A)? - ANSWER The sum of the
masses of protons and neutrons in the nucleus
What are isotopes? - ANSWER Atoms of an element that have different
atomic masses
What was the Bohr Atomic Model? - ANSWER Assumes electrons
revolve around nucleus in discrete orbits. Electrons are placed in energy
levels or states
What was the Wave-Mechanical Model? - ANSWER Electrons do not
have discrete levels and positions. Position is probability of an electron
being at a particular location. Electron cloud
, What do the four quantum numbers characterize? - ANSWER 1. Size
2. Shape
3. Spatial orientation of the electron's probability density
4. Spin moment of the electron
What is a ground state? - ANSWER When all of the electrons occupy
the lowest possible energies
What is a valence electron? - ANSWER Electrons occupying the
outermost filled shell
What are the three types of chemical bonds? - ANSWER 1. Ionic
2. Covalent
3. Metallic
What types of material are used in an ionic bond? - ANSWER Between
metallic and nonmetallic elements
Is ionic bonding non-directional? Why? - ANSWER Yes, equal in all
directions and number of positive and negative ions as neighbors
What are some ionic bond characteristics? - ANSWER - Bonding energy
is high
- High melting temperature
- Hard
- Brittle
- Electrical and thermally insulative
What is a covalent bond? - ANSWER Stable electron configurations that
occur by sharing electrons between atoms
Is covalent bonding non-directional? Why? - ANSWER No, bonding
occurs between specific atoms
Are valence electrons bound to a particular atom in metallic bonds? -
ANSWER No, they are free to drift forming an electron cloud
relationship between the structures and properties of materials
What are three classifications of materials? - ANSWER Metals,
ceramics, and polymers
What are metals? - ANSWER Non-localized electrons and good
conductors of electricity and heat; strong; deformable
What are ceramics? - ANSWER Examples: clay, cement, and glass.
Insulative to the flow of electricity and heat; resistant to high
temperatures and harsh environments; hard; brittle
What are polymers? - ANSWER Organic components comprised of
carbon, hydrogen, and other non-metals
What makes up an atomic number (Z)? - ANSWER The number of
protons in the nucleus
What makes up an atomic mass (A)? - ANSWER The sum of the
masses of protons and neutrons in the nucleus
What are isotopes? - ANSWER Atoms of an element that have different
atomic masses
What was the Bohr Atomic Model? - ANSWER Assumes electrons
revolve around nucleus in discrete orbits. Electrons are placed in energy
levels or states
What was the Wave-Mechanical Model? - ANSWER Electrons do not
have discrete levels and positions. Position is probability of an electron
being at a particular location. Electron cloud
, What do the four quantum numbers characterize? - ANSWER 1. Size
2. Shape
3. Spatial orientation of the electron's probability density
4. Spin moment of the electron
What is a ground state? - ANSWER When all of the electrons occupy
the lowest possible energies
What is a valence electron? - ANSWER Electrons occupying the
outermost filled shell
What are the three types of chemical bonds? - ANSWER 1. Ionic
2. Covalent
3. Metallic
What types of material are used in an ionic bond? - ANSWER Between
metallic and nonmetallic elements
Is ionic bonding non-directional? Why? - ANSWER Yes, equal in all
directions and number of positive and negative ions as neighbors
What are some ionic bond characteristics? - ANSWER - Bonding energy
is high
- High melting temperature
- Hard
- Brittle
- Electrical and thermally insulative
What is a covalent bond? - ANSWER Stable electron configurations that
occur by sharing electrons between atoms
Is covalent bonding non-directional? Why? - ANSWER No, bonding
occurs between specific atoms
Are valence electrons bound to a particular atom in metallic bonds? -
ANSWER No, they are free to drift forming an electron cloud
