Unit 3 Chemistry

Define atom

The smallest particle of an element that retains properteies of the elemtn

Why is an atom neutral

The number of protons and electrons are equal in a neutral atom

Define electron cloud

The area outside of the nucleus containing electrons

Electrons

Negatively charged subatomic particles found outside the nucleus 

What determines which element an atom is

The number of protons/ Atomic number

Define neutrons 

Subatomic particle found in the nucleus with no charge 

Atomic number

The number of protons of an element and electrons in an neutral atom

Mass number

Protons plus neutrons

What is equal to one amu

1/12 the mass of a carbon-12 atom

How are cations formed

Electrons are lost, making a postive ion

How are anions formed

Electrons are gained, making a negative ion

What type of element generally forms cations 

Metals 

How are isotopes of the same element alike and how are they different

They have the same number of protons but different neutrons/masses

How did Rutherfords model improve Thomsons model

he determined that most of the atom is empty space and the positive nucleus is very dense, small with only little volume and electrons circle it

Conversions 

1 Mole\6.022 × 10²³ molecules, units, etc. 

Mass in g/1 mole 

1 mole/ 22.4 L