 # Atomic Structure.

## Presentation on theme: "Atomic Structure."— Presentation transcript:

Atomic Structure

Atom Basic unit of matter Made of subatomic particles

Element Substance made of same type of atom

Protons Positive Charge Located in the nucleus Mass = 1 amu
Helps make up the mass of an atom # of protons never changes for an element Same as atomic number

Neutrons No Charge Located in the nucleus Mass = 1 amu
Helps make up the mass of an atom Can differ in atoms of the same element How to Calculate Neutrons Mass # - Atomic # = Neutrons

Electrons Negative Charge Located in the electron cloud Mass = 0 amu
Surrounds the nucleus Move very fast! Mass = 0 amu Does not really count towards an atom’s mass In neutral atoms, electrons = protons

Atomic Number Special for every element
Tells # of protons (and electrons) Located on the periodic table (whole number)

Atomic Mass Located on periodic table
Has decimals Average mass of the element’s isotopes

Mass Number Protons + Neutrons Whole Number (rounded atomic mass)

Practice How many protons does nitrogen have?

Practice What is the atomic mass of calcium?

Practice What is the mass number of calcium?

Practice How many neutrons are in chlorine?

Practice Name of Element: Atomic Number: Atomic Mass: Mass Number:
Protons: Neutrons: Electrons:

Practice Name of Element: Atomic Number: Atomic Mass: Mass Number:
Protons: Neutrons: Electrons:

Practice Name of Element: Atomic Number: Atomic Mass: Mass Number:
Protons: Neutrons: Electrons:

Just How Small Are Atoms?

Isotopes Same element with different numbers of neutrons; therefore, different masses EX: Carbon-12 Carbon-14 6 12 C C

Practice How many neutrons in Potassium-39 Potassium-41 Fluorine-19

Practice Ni-60 Protons? Electrons? Mass number? Neutrons?

Practice Magnesium-26 Protons? Electrons? Mass number? Neutrons?

Practice P Protons? Electrons? Mass number? Neutrons?

Ions Charged atom Gain or lose 1 or more electrons
Proton number does not change

Practice How many electrons in a neutral atom of Na?
How many protons in Na? How many electrons in Na +1

Practice How many electrons in a neutral atom of S?
How many protons in S? How many electrons in S -2?