School Reviewers

G8: Science

By: DanielleBihasa

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States of Matter:

Solid - has definite shape and volume

Liquid - has definite volume but takes the shape of its container

Gas - has neither definite volume nor a definite shape

Phases of Matter:

Melting- solid to liquid
Freezing- liquid to solid
Vaporization- liquid to gas
Condesation- gas to liquid
Deposition- gas to solid
Sublimation- solid to gas
Ionization- gas to plasma
Recombination- plasma to gas

Physical Change- dosent change the substance's composition and can be reversed

Chemical Change- changes the subtances composition creating new substance and cannot be reversed

Laws of Chemical Combination:

Law of Conservation of Mass (Lavosier):
-matter was neither created nor destroyed, does not change during chemical reaction

Law of Definite Composition (Joseph Proust):
-chemical compound are composed and defined ratio of element as determined by mass

Law of Multiple Proportion (Dalton):
-when two elements are combined to yeld more than 1 compound, the mass of 1 element which is combined with a fixed mass of the other element affair in a ratio of small whole numbers.

Atom- Smallest constitiuent unit of ordinary matter

Parts of the Atom
Protons- positive
Neutrons- no charge
Electrons- negative

Daltons Atomic Theory
- All matter is made up of atoms. They are invisible and indistructable.
- All atoms in a given element are identical in mass and properties
- Compounds are elements formed by a combination of two or more different kinds of atoms.

Atomic Number- no. of protons in the nucleus of an atom

Atomic Mass- mass of an atom of a chemical element expressed in atomic mass units

Isotopes- are variants of a particular chemical element which differ in neutron no.

Ions- is a particle that has a non-zero net electrical charge

Anions- gains electron
Cations- loses electron

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