Chapter 2.1 NotesSeptember 8, 2014

• Grab a textbook and return quietly to your seat

• Write your EQ at the top of page 26 in your journal “What is the relationship between elements and compounds?”

When you enter…..• Grab a textbook and return quietly to your seat

• Write your EQ at the top of page 26 in your journal “What is the relationship between elements and compounds?”

Vocabulary Use KIM Notes to define the following

words:1. Substance2. Molecule3. Compound4. Chemical Formula5. Ratio

Matter Matter is anything that has mass and

takes up space A substance is a single kind of matter

that is pure meaning that it always has a specific makeup and set of properties

Examples- sugar, table salt Non-examples- butter, milk

Physical Properties Properties of a pure substance that can

be observed without changing it into another substance

Examples: Hardness, Texture, Color, State of Matter, Flexibility, Conductivity

Diamonds are the hardestnatural material

Flexibility

Chemical Properties A characteristic of a pure substance that

describes its ability to change into a different substance

Properties include flammability and reactivity

Question: What must you do to observe a

chemical change?

Think….Pair…..Share Helium does not react with any other

substance. Is it accurate to say that helium has no chemical properties?

Elements Are the simplest substances All matter in the universe is made up of

slightly more than 100 elements An element cannot be broken down into

any other substance by chemical or physical means

An atom is the basic particle from which all elements are made

When atoms combine Atoms combine with a chemical bond to

form larger particles called molecules- two or more atoms held together by a chemical bond

https://www.youtube.com/watch?v=IOXxFaHbIXg

Compounds Most elements are found in nature combined

with other elements. A compound is a pure substance made of two or

more elements chemically combined in a set ratio

(Read Math Skills Box p.40) Represented by a chemical formula which shows

the elements and the ratio of atoms Compounds have different properties from those

that are uncombined elements (Ex: Na is very reactive, table salt-NaCl- is not)

Mixtures Most materials are not pure substances

(elements or compounds) A mixture is made of two or more

elements or compounds that are not chemically combined or combined in a set ratio

Each substance in a mixture keeps its individual properties

Types of Mixtures

Heterogeneous You can see the

different parts

Homogeneous So evenly mixed

that you can’t see the different parts

Example: Solution

Question… Why is it correct to say that sea water is

a mixture?

Scientific Scramble

Video https://www.youtube.com/watch?v=

AfXxZwNLvPA