ELEMENTS, COMPUNDS, AND MIXTURES

INTRODUCTION

• An element is a pure substance
• A compound is two elements together
• A mixture is two substances come together
• But don't make a new one

ELEMENTS

• One or more atoms of one kind make up a element
• One common example of a element is oxygen (O)
• There are 115 known elements and 90 are naturally occuring
• There is hydrogen, nitrogen, carbon, and helium

COMPOUNDS

• A compound is made up of 2 or more elements
• It is chemically combined to make a new substance
• An example is (Fe) which is iron and oxygen makes rust
• Another is HO, which is 1 hydrogen and 1 oxygen
• FeH and NaO are some other examples

MIXTURES

• Heterogeneous does not look all the same
• You can see each part
• Homogeneous does look all the same
• You can not see all the parts
• Ex: koolaid, tea, lemonade, salad, and cereal

5 MOST COMMON ELEMENTS IN EARTH'S CRUST

• 46.6% oxygen
• 27.7% silicon
• 8.1% aluminum
• 5.0% iron
• 3.6% calcium