Dalton's Atomic Theory

All Matter is Made of Atoms

1

Indivisible Particles

Atoms: smallest unit of matter

2

Indestructible Nature

Cannot be created or destroyed

3

Building Blocks

Form all substances in universe

Identical Atoms of an Element

Size

Consistent atomic radius within

element

Mass

Uniform atomic mass for each

element

Chemical Properties

Same reactivity and bonding

behavior

Differences Between Elements

Element

Size

Mass

Properties

Hydrogen

Small

Light

Highly reactive

Carbon

Medium

Moderate

Forms many

compounds

Gold

Large

Heavy

Inert,

conductive

Compounds: Simple Whole-Number Ratios

Water (H2O)

2 hydrogen : 1 oxygen

Carbon Dioxide (CO2)

1 carbon : 2 oxygen

Methane (CH4)

1 carbon : 4 hydrogen

Chemical Reactions: Atomic
Rearrangement

1

Reactants

Initial molecules or compounds

2

Reaction

Bonds break and reform

3

Products

New compounds with rearranged atoms

Conservation of Mass

1

Before Reaction

Total mass of reactants

2

During Reaction

Atoms rearrange, mass unchanged

3

After Reaction

Total mass of products equal

Impact on Modern Chemistry

Atomic Structure

Foundation for understanding subatomic particles

Chemical Bonding

Explains formation of molecules and compounds

Stoichiometry

Enables quantitative analysis of reactions

Periodic Table

Organizes elements based on atomic properties