The Building Blocks of All Substances

A Tree What are its parts?

• leaves• branches • roots • trunk • stems • etc.

A LeafWhat are its parts?

• veins • covering• chlorophyll • (green pigment)

• etc.

ChlorophyllWhat are its parts (elements)?

• Magnesium• Nitrogen• Carbon• Hydrogen• Oxygen

ElementsWhat are their parts?

Elements are pure substances that cannot be broken down into simpler substances.

For chlorophyll, the elements are:C = carbonH = hydrogenO = oxygenMg = magnesiumN = nitrogen

ElementsHow are they named?

All the elements we know about at this time are listed on the current periodic table.

There are about 90 naturally occurring elements. Some are named after people, places, or from Latin or Greek names.

Since there are only 26 letters in our alphabet, a systematic way to write their symbols was developed by scientists.

Elements3 Naming Rules

Rule 1: PRINT all symbols. Rule 2: If there is only one letter, that letter

is always a capital. Example: H for hydrogen

Rule 3: If there are two letters, the first letter is a capital and the second is lower case. Example: He for helium

ElementsCorrect or Incorrect

CA

CACaCa

CAcA

ElementsCorrect

CACACa

CaCA

cA