What’s the MATTER: Classify Changes of Matter

Matter, Classify Changes of Matter At the conclusion of our time together, you should be able to: 1. Characterize various changes of matter 2. Recognize that a change of state in matter is a physical change

Interesting Signs:

Physical Physical Change  A change in matter from one form to another without changing its chemical properties  (most can be reversed)  No change in atoms/molecules

Physical Change  Examples = Change in state or phase change Dissolving Compressing Light emission/absorption Electrons passing through metals

Physical Change More Examples =  boiling of a liquid  melting of a solid  dissolving a solid in a liquid to give a homogeneous mixture  making a solution

Chemical Chemical Change Bonds are made / broken Change in oxidation states Bonds are made / broken Change in oxidation states Cl Li +1

Examples of Chemical Change  Chemical change or chemical reaction — transformation of one or more atoms or molecules into one or more different molecules. Burning hydrogen (H 2 ) in oxygen (O 2 ) gives H 2 O.Burning hydrogen (H 2 ) in oxygen (O 2 ) gives H 2 O.

Sure Signs of a Chemical Change “Chemists Get Practice Trying Labs”  Color Change  Gas Produced (not from boiling!)  Precipitate – a solid formed by mixing two liquids together  Temperature Change  Light

Will This be on the Test????

Remember the Law of Conservation of Mass  In a physical change or a chemical reaction, mass is neither created or destroyed (Antoine Lavoisier)

Matter, Classify Changes of Matter Let’s see if you can: 1. Characterize various changes of matter 2. Recognize that a change of state in matter is a physical change

Physical vs. Chemical Change  Examples: melting flame produced paper cut dissolving salt in water tarnishes in air physical chemical physical chemical

 Examples: rusting iron mixing mud and water burning a log freezing water grinding spices Physical vs. Chemical Change chemical physical chemical physical

 A difference between physical change and chemical change is that 1. chemical change involves energy while physical change does not. 2. physical change involves energy while chemical change does not. 3. different kinds of molecules are present after a physical change but not after a chemical change. 4. different kinds of molecules are present after a chemical change but not after a physical change

In making a pizza, which process involves a chemical change? 1.Mixing spices for the sauce 2.Slicing pepperoni for the topping 3.Spreading cheese on the pizza 4.Baking the dough to form the crust In making a pizza, which process involves a chemical change? 1.Mixing spices for the sauce 2.Slicing pepperoni for the topping 3.Spreading cheese on the pizza 4.Baking the dough to form the crust

All You Really Need To Know You Can Learn From Noah's Ark 11. Remember that the ark was built by amateurs; the Titanic was built by professionals. 12. Remember that woodpeckers inside are a larger threat than the storm outside.

What’s the MATTER, Properties of Matter

Matter, Properties of Matter At the conclusion of our time together, you should be able to: 1. Explain the difference between the extensive and intensive properties and other types of properties 2. Distinguish between a physical property and chemical property

Too late to learn this stuff???

The Nature of Matter Chemists are interested in the nature of matter and how this is related to its atoms and molecules. GoldMercury

Chemistry & Matter  We can explore the MACROSCOPIC world — what we can see —  to understand the PARTICULATE worlds we cannot see.  We write SYMBOLS to describe these worlds.

A Chemist’s View 2 H 2 (g) + O 2 (g) --> 2 H 2 O(g) MacroscopicMacroscopic SymbolicSymbolic ParticulateParticulate

Septic Tank Humor

Properties of Matter  2 Types: Extensive – depend on the amount of the sample Always involves a number with unit Examples =volume mass length

Properties of Matter (cont.) Intensive – does not depend on the amount of the sample Usually does not involve a number Examples =density melting, boiling point malleability ductility color odor

Properties  Every substance has a unique set of properties (characteristics that identify that substance)  Physical Properties- Properties that can be measured without changing the identity and composition of the substance

Physical Property Examples- Color Odor Density Melting Point Boiling Point Hardness Solubility

A Stick What Do You Call a Boomerang That Doesn't Work?

Graphite — this layer structure of carbon atoms reflects its physical properties. List Some Physical Properties of:

Chemical Properties  Properties that describe the way a substance may change to form other substances  Only observed when a chemical reaction takes place

Chemical Property Examples  Combustible  Reactive with water or acid  Flammable  Corrosive  Decomposes in air

Do I Have to Learn this Stuff???

Physical vs. Chemical Properties  Physical Properties- Properties that can be measured without changing the identity and composition of the substance  Chemical Properties- Properties that can be measured by changing the identity and composition of the substance

Matter, Properties of Matter Let’s see if you can: 1. Explain the difference between the extensive and intensive properties and other types of properties 2. Distinguish between a physical property and chemical property

Design a Hypothesis

Properties of Matter  2 Types: Extensive – depends on the amount of the sample Intensive – does not depend on the amount of the sample

Physical vs. Chemical Properties  Physical Properties- Properties that can be measured without changing the identity and composition of the substance  Chemical Properties- Properties that can be measured by changing the identity and composition of the substance

Physical vs. Chemical Property  Examples: melts at 55 o F flammable will tear easily will dissolve in water will tarnish physical chemical physical chemical

 Examples: will rust mixture can be separated by boiling burns freezes at -20 o C can be crushed Physical vs. Chemical Properties chemical physical chemical physical

Familiar Saying A rotating lithoidal fragment never accrues lichen. A rolling stone gathers no moss!!

The End!!!