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
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Mirror. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $13.49. You're not tied to anything after your purchase.