Notes SPI 0807.9.3 Elements and Compounds

What Is An Element? Each individual element is a unique particle called an atom So in other words… elements are the different types of atoms An element is a pure substance that CANNOT be broken down into a simpler substance by CHEMICAL means. In other words…you CANNOT change one element into a different element with a chemical reaction

ExampleLithium is an element.

Here is one lithium atom.

3

LiLithium

6.9

Science

Examples of Elements

Notes SPI 0807.9.3 Elements and Compounds Science

H

Na

Ca

-represents one sodium atom

-represents one hydrogen atom

-represents one calcium atom

The element hydrogen

The element sodium

The element calcium

More About Elements The chemical symbols for elements always start

with one capital letter These chemical symbols can be followed by one(or more) lower case letters

Ex: B, C, N, O, F, etc

Ex: He, Li, Be, Mg, etc

Sodium and Chlorine

Carbon and Oxygen

Carbon, Hydrogen, & Oxygen

Notes SPI 0807.9.3 Elements and Compounds Science

NaCl

CO2

C6H12O6

(Sodium Chloride

(Carbon Dioxide)

(Glucose)

What Is a Compound? …consists of two or more different elements that are

chemically bonded via a chemical reaction to form a new substance.

The properties of the new substance are different from the substances that you started with.

Examples of Compounds

…note that it has more than 1 capital letter

…note that it has more than 1 capital letter

…note that it has more than 1 capital letter

Notes SPI 0807.9.3 Elements and Compounds Science

Examples of Compounds

H2O

C12H22O11

CH3COOH

Chemical formulas for compounds always contain more than one capital letter.

This is the compound called water

This is the acidic compound called vinegar

This the compound called table sugar

This is how you can tell the difference between an element and a compound… count the number of capital letters!

More About Compounds

When you combine two or more substances together, if no chemical reaction occurs, then it is called a mixture.

NotesSPI 0807.9.4

Mixtures or Compounds

Any changes you observe in a mixture are only physical changes… no new substances are formed.

Science

…consists of two or more different elements that are chemically bonded in a chemical reaction to form a new substance.

Mixtures can be fairly easily separated back into their parts

What is a Mixture?

Air Steel Salt Water BloodMixture Examples:

Compounds CAN NOT be easily separated back into their parts

Milk

What is a Compound?

Compound Examples: NaCl CO2 C6H12O6 H2O

NotesSPI 0807.9.4

Mixtures or Compounds

EXAMPLE: A Mixture

Science

Air

Nitrogen

7N14.0

Oxygen

8O16.0

Argon

18Ar39.9

Composition of Air: 78% Nitrogen, 21% Oxygen, 1% Argon and other gases

When these ingredients are mixed together no chemical reaction occurs

NotesSPI 0807.9.4

Mixtures or Compounds

EXAMPLE: AMixture

Science

Blood

Blood Ingredients: 55% Plasma (consists of 90% water, 8% Protein, 2% other)

45% Red/White blood cells and Platelets

When these ingredients are mixed together no chemical reaction occurs

NotesSPI 0807.9.4

Mixtures or Compounds

EXAMPLES: A Mixture

Science

Milk

Milk Ingredients: 88% Water, 5% Carbohydrates, 3% Fat, 3% Protein, 1% Minerals

When these ingredients are mixed together no chemical reaction occurs

NotesSPI 0807.9.4

Mixtures or Compounds

MORE EXAMPLES: Mixtures

Science

CementSalad

Soup

Cement Soup Salad

No chemical reaction occurred when these mixtures were formed

NotesSPI 0807.9.4

Mixtures or Compounds

MORE EXAMPLESMixtures

Science

Tea Kool-Aid

Tea

Energy Drinks

Soft DrinksKool-Aid Drinks

No chemical reaction occurred when these mixtures were formed

NotesSPI 0807.9.4

Mixtures or Compounds Science

2) If no chemical reaction occurred when youcombined the substances together, then it is a mixture.

How do I know if something is a mixture or not?

1) Mixtures can be fairly easily taken back apart.

Two Ways

Note: Look at the next slide to see ways to take mixtures apart.

Note: Look at the next slide after that to see ways to determine if a chemical reaction occurred.

NotesSPI 0807.9.4

Mixtures or Compounds Science

By hand By filtration

By distillation By magnetism

How to separate apart mixturesFour examples