Chemistry Formative Flashcards
Define atoms
Very small particles that make up all matter in all substances
Define elements
2 or more atoms of the same type bonded together
Key properties to describe elements
Dense
Brittle
Malleable
Conductor
Lustrous or shiny
Ductile
Define dense
A material that contains a lot of particles in a small space
Define brittle
A material that is delicate and easily broken
Define malleable
A material that can be bent or shaped
Define conductor
A substance that allows heat or energy to flow through it
Define lustrous or shiny
Able to reflect light
Define ductile
A material that can be easily bent without breaking and drawn into wires
Single-atom
An example is helium which exists as a single atom
Molecules
2 or more atoms bonded together
Lattice
Atoms bonded together in a framework
Properties of metals
Shiny
Solid at room temperature (except mercury)
Good conductors of heat and electricity
Malleable
Ductile
Properties of non-metals
Dull
Poor conductors
Brittle
compound
2 or more different atoms bonded together
Pure substance
only made up of one chemical (e.g. water)
Mixture
Made up of 2 or more chemicals (e.g. air)
Physical change
- No new substances formed
- Easy to reverse
Bonds do not change
e.g. inc melting
- Easy to reverse
Chemical change
- New substances formed
- Hard to reverse
- Bonds break and form
e.g. frying an egg
