Elements and Compounds A Mr. Mularella Presentation
The 4 Ancient Elements Earth Fire Air Water
There are currently 118 elements that have been identified though only 88 of them are naturally occurring.
Elements in the Universe
In our universe, hydrogen makes up 75% of all matter!
Helium makes up about 20% with oxygen being the 3 rd most abundant element.
All of the other elements are relatively rare in the universe.
Elements in the Earth
In the Earth’s crust, oxygen is the most abundant element (46.6%).
Silicon is the second most abundant element (27.7%).
Aluminum (8.1%), iron (5.0%), calcium (3.6%), sodium (2.8%), potassium (2.6%). and magnesium (2.1%) complete the list of elements that account for approximately 98.5% of the total mass of the earth's crust.
Elements are a pure substance.
Made of only one kind of material, has definite properties, and is the same all throughout.
Elements are the simplest pure substance.
They cannot be broken down into simpler substances without losing their identity.
Elements and Atoms
The smallest particle of an element that has the properties of that element is called an atom .
Atoms: the building blocks of matter.
Atoms of the same element are alike; atoms of different elements are different.