Define and give an example of: Compound / Molecule
A Pure Substance and compound of two or more atoms of different elements, ex H2O.
Define and give an example of: Element
A pure substance that cannot be broken down into simpler substances, ex Hydrogen.
Define and give an example of: Atom
The smallest unit of an element, ex Copper Atom.
Define and give an example of: Mixture
Substances together which are NOT combined chemically, ex Salad.
A negative charge in an atom.
A positive charge in an atom.
Describe the difference between a physical and chemical change?
A chemical change effects the chemicals, while physical does not.
Give three example of physical change?
Give three examples of a chemical change?
What is Law of Conservation of Matter (Mass)?
Matter cannot be created or lost.
What are three signs (indicators) of a chemical reaction?
What is precipitate?
a solid that forms and settles out of a liquid mixture.
Where is the atomic # found and what does it mean?
The top (or lowest number) and it represents the amount of protons in an atom.
Where is the mass # found and what does it mean?
Found at the bottom (or biggest number), and It represents the amount of protons and neutrons.
How do you calculate the # of neutrons in an atom?
Subtract the atomic number from the atomic mass.
What is the difference between a period and a group on the periodic table?
Periods are vertical and groups are set horizontally. Also, groups are related by have equal valence electrons.
What is another name for a group on the periodic table?
Family is another name for groups on the periodic table.
What is a closed system?
A system during an experiment where nothing can be added or can escape.
What are valence electrons and why are they important?
They are the "outside" electrons on the outer-most energy level.
How many (H)'s and (O)'s are in 4H20?
Eight (H)'s and four (O)'s.
How many (C)'s and (O)'s are in 3CO2?
Three (C)'s and six (O)'s.