Emission Spectra, Atomic Structure, Atomic Number, Isotopes and Mass Number ( March 5 2010)

Emission Spectra
-each element gives of a specific colour of light
-these are known as emission spectra
-unique to each element
-If electrons absorb energy they can be bumped to a higher level
-when they fall to a lower level they release that energy as light















Atomic Structure
- Atoms are mad up parts called subatomic particles
Protons (positive)
Neutrons ( neutral)
Electrons (negative)

Particle ( mass, charge, locations)
Proton ( 1, +1, nucleus)
Neutron ( 1, 0, nucleus)
Electron (1 divided by 1837, -1, outside)


Atomic Number
-number of protons

Isotopes

-The number of protons determine the type of element

-Changing the number of neutrons changes the isotope of the element

-All isotopes have the same chemical properties

Mass Number
-total protons and neutrons
symbol- A
- different isotopes have different masses
mass number = atomic number + number of neutrons