Chemical Changes

Compound: a chemical combination of two or more elements.


Chemical bond: a link that atoms or electrically charged particles can form with each other.


Chemical formula: a way of using letters and numbers to show much of each element is in a substance.


Ion: an electrically charged particle with unequal numbers of protons and electrons.

Molecule: a group of bonded atoms that acts like a single particle.

Chemical propety: a way of describing how a substance changes chemically with other substances.


Exothermic: a reaction that give off heat.

Endothermic: a reaction that absorbs heat.

Elements and Atoms

Element: a substance that cannot be broken down any further into anything simpler.


Atom: the smallest particle of an element that has the same chemical properties as the element.



nucleus: an atoms dense center, where most of its mass is.


Electron: a negatively charged particle that moves around an atoms nucleus.

Proton: a positively charged particle inside an atoms nucleus.


Neutron: a particle with no charge inside an atoms nucleus.

Atomic number: the number of protons in an atom.

Metal: any of a group of elements that conduct heat and electricity, is shiny and bendable.

Physical Properties

1. Matter: any solid, liquid, or gas.

2. Mass: Amount of matter in an object 

3. Volume: the amount of space an object takes up.

4. Density: The amount of mass in a certain volume of material.

5. Physical Property: A property that can be observerd without changing the identity of a substance.

6. Physical Change: a charge in size, shape, or state without forming a new substance.

 7. Solution: a mixture of one substance dissolved in another so that the properties are the same throughout.

8. Chemical Change: a change  in matter that produces a new substance with different properties from the original.