What is Matter?

• CHEMISTRY- the scientific study of the composition, structure, and properties of matter and the changes that matter undergoes

• MATTER- anything that has mass and take up space

• Ex of matter: (class will give examples and write them down)

• Light and sound are matter? Why?

• ELEMENT- a substance that cannot be separated or broken down into simpler substances by chemical means

• Each element is made of only one kind of ATOM

• ATOM- smallest unit of an element that maintains the properties of that element

• Symbols for elements are always a single capital letter or a capital letter followed by a lowercase letter (ex: carbon- C, iron- Fe, copper- Cu, aluminum- Al)

• Earth and the human body differ in the kind and proportion of elements are composed of

• COMPOUND- a substance made of atoms of two or more different elements that are chemically combined (give one example)

• A water molecule can be represented by a formula, physical models, or computer images

• Every compound is different from the elements it contains (ex: the elements hydrogen oxygen, and nitrogen are colorless gases, but when combine with carbon to form nylon, the strands of nylon are flexible solid)

• MOLECULE- the smallest unit of a substance that keeps all of the physical and chemical proprieties of that substance (the smallest unit of a substance that behaves like a substance)

• A water molecule is made of two hydrogen and one oxygen atom

• Most molecules are made of atoms of different elements, but also be made of atoms of the same element:

• CHEMICAL FORMULA- a combination of a chemical symbols and numbers to represent a substance

• Ex: Indigo is the dye first used to turn jeans blue, the chemical formula of indigo is shown in fig., and it is made of 4 elements and 30 atoms

• In a chemical formula, the number of atoms of each element is written after the element’s symbol

• Numbers placed in front of a chemical formula show the number of molecules

• Three molecules of table sugar are written as: 3C12H22O11, each molecule of sugar contains 12 carbon atoms, 22 hydrogen atoms and 11 oxygen atoms

• Ex: How many elements and atoms have : acetic acid C2H4O2, glucose C6H12O6, table salt (sodium chloride) NaCl, water H2O

• PURE SUBSTANCE- a sample of matter, either a single compound that has definite chemical and physical proprieties

• Pure= not mixed with anything• Pure substance is matter that has a fixed

composition and definite proprieties• Ex:- water is a pure substance made up of

elements hydrogen and oxygen, which are chemically combined

- grape juice, the components, such sugar and water are not chemically combined

• Grape juice is a MIXTURE

• A MIXTURE- a combination of two or more substances that are not chemically combined

• A mixture may have proprieties that are similar to the pure substance that form it (Ex: grape juice: liquid (water), sweet (sugar)

• Some mixtures are made by putting solids and liquids together

Lab: determine differences between given mixtures

• Combine, sugar with water, flour with water, sand with water, and syrup with water

• Write in the table observations, and write down the conclusions

Draw a table:Substance 1 Substance 2 Observations

• HOMOGENEOUS ( homo- the same)- the substance are evenly distributed (a sample from the bottom of a glass should have the same composition as a sample from the top)

• HETEROGENEOUS (hetero: different)- the substances aren’t mixed uniformly, and are not evenly distributed

• From the lab examples, which examples are homogeneous, and which are heterogeneous, write down the reason