#### Atomic Structure and Descriptive Numbers

Smallest particle of an element that can exist alone while still retaining the properties of that element

Atom

Main parts of the Atom include: (2)

1. Nucleus
2. Electron Cloud

Nucleus contains:

protons and neutrons

What are the charges of the subatomic particles?

Proton (+)- positive charge
Electron (-)- negative charge
Neutron (o)- no charge

True/False:
An electron is the smallest subatomic particle.

True

How many shells make up the electron cloud?

7

Electron Cloud contains:

protons and electrons

How many electrons can each shell hold?

1st = 2 electrons
2nd = 8 electrons
3rd = 18 electrons
4th-7th = 32 electrons

How do you find the atomic number of an element?

# of protons

The # of protons and the # of electrons is equal to the _____ _____?

Atomic number

True/ False:
The atomic number is used to identify an element.

True

What is another name for the atomic weight?

Atomic mass

True/False:
The atomic weight is usually a decimal.

True

True/False:
Mass number = # of protons + # of neutrons

True

# of neutrons = ___________ - ____________

Mass number - Atomic number