1. Elements, Compounds, and Mixtures

2. What are the basic differences? Element Any substance that contains only one kind of atom Cannot be broken down Compound Consists of atoms of two or more different elements Can be broken down Mixture Consists of two or more different elements/compounds Can be separated

3. What is an element? Pure Substance Made up of one kind of atom (smallest unit) Homogeneous in structure Cannot be broken down or separated Identified by a chemical symbol (ex. C) Classified as a metal, nonmetal, or metalloid Examples: Hydrogen, Helium, Oxygen, Carbon, Sodium, Etc.

4. Types of Elements

5. What is a compound? Is a pure substance Made up of 2 or more types of elements Is homogeneous in structure Cant be broken down or separated by Physical means Smallest unit is a molecule Identified by a chemical formula (H 2 O) Created through a chemical change Held together by a chemical bond Examples: Sugar, Rust, Water, Carbon Dioxide

6. What is a mixture? Is a not a pure substance Made up of 2 or more types of elements Can be broken down or separated by physical means Smallest unit is a molecule Identified by the ingredients in contains Classified as homogeneous or heterogeneous Physically held together with no chemical bonds Examples: Sugar water, blood, granite, cereal with milk, granola bar

7. Types of Mixtures Homogeneous Uniformly mixed on an atomic/molecular level Parts do not appear separate Difficult to take apart Examples: Air (includes N 2, O 2, H 2 O, CO 2 ), Blood (includes red blood cells, white blood cells, plasma, and platelets) Heterogeneous Not uniformly mixed on an atomic/molecular level Parts appear separate Easy to take apart Examples: Salt and pepper, chocolate chip cookies

8. Practice Classify the following as an element, compound, or mixture (heterogeneous or homogeneous) Carbon = Hydrogen = Oxygen = Sugar (C 12 H 22 O 11 )= Sugar Water that’s completely mixed = Sugar Water with sugar at the bottom =

9. Practice Classify the following as an element, compound, or mixture (heterogeneous or homogeneous) Carbon = Element Hydrogen = Element Oxygen = Element Sugar (C 12 H 22 O 11 )= Compound Sugar Water that’s completely mixed = Homogeneous Mixture Sugar Water with sugar at the bottom = Heterogeneous Mixture