UNIT: Matter Objectives: Lesson 1 of 4 You will understand the difference between the 3 most common states of matter You will understand the difference between Physical and Chemical Properties You will understand the difference between Physical and Chemical Changes TOPIC: Properties of Matter

Quickwrite In 1-2 sentences answer one of the questions below: When a banana begins to brown, what do you think is happening??? When a substance such as water freezes, do you think this alters or changes the water molecules???? If you break a piece of glass, do you think this alters or changes the physical shape?

A solid is a state of matter that has a definite shape and volume The atoms are tightly packed (more dense) and are not free to move Lowest energy state of matter States of Matter Like water, all substances exist in three states of matter: solid, liquid, or gas A liquid is a state of matter that has a definite volume but takes the shape of it’s container The particles in a liquid are also tightly packed but they are free to move around A gas is a state of matter with no definite shape or volume, it takes on the shape of it’s container In a gaseous state, the atoms are vastly spread apart from one another (low density) and are free to move around Highest energy state of matter

What are the 3 states of matter? SolidLiquidGas State of matter that has a definite shape and volume State of matter that has a definite volume but takes the shape of it’s container State of matter with no definite shape or volume, takes on the shape of it’s container Atoms are tightly packed (high density state of matter) & are NOT free to move Atoms are tightly packed but are free to move around Atoms are vastly spread apart (low density state of matter) and are free to move around Lowest energy state of matter Highest energy state of matter

Physical vs. Chemical Properties A physical property is a characteristic of a substance that can be observed without changing the substance For example consider element number 26, Iron Iron has many physical properties, for example, because it is a metal, it is shiny or lustrous Another physical property, if you recall from our last unit is density; Iron has a density of 7.8 g/mL As many of you know, iron is also magnetic All of these characteristics are properties that we can observe without changing the actual substance

Physical vs. Chemical Properties Every substance has both physical and chemical properties A chemical property describes how a substance changes into one or more different new substances One again, consider Iron Iron readily reacts with oxygen By doing so, it forms rust, an entirely new chemical with it’s own set of properties Notice, Iron has changed into a new substance, rust or Iron Oxide (Fe 2 O 3 ) Fe + O 2  Fe 2 O 3

What is the difference between physical and chemical properties? A physical property is a characteristic of a substance that can be observed without changing the chemical nature of a substance – Example: Iron is magnetic and has a density of 7.8 g/mL A chemical property describes the tendency of a substance to transform into one or more different new substances – Example: Iron reacts with oxygen to from rust: Fe + O 2  Fe 2 O 3

Physical Properties of Metals Of all the elements in the periodic table, most are metals Metals have many properties that we use in our everyday lives For example, metals are shiny or lustrous They are also malleable, allowing metals to be bent or hammered without breaking or cracking Metals also conduct electricity

What are some physical Properties of metals? Some Physical Properties of metals include: – Shiny or lustrous – Malleable and can be bent, hammered and flattened without breaking or cracking – Conduct Electricity

Physical vs. Chemical Changes All changes in matter are either physical or chemical A physical change is the change that occurs in the physical properties of a substance without altering its chemical composition Clues that accompany a physical change include: – A change in shape or physical appearance – A change in state (solid, liquid, or gas) For example, ice melting is a physical change because a change of state is taking place Notice, during the physical change, the chemical composition of water (H 2 O) does not change Crushing an aluminum can is another example of physical change because you are altering its physical shape Notice during the change, Aluminum is still Aluminum before and after you crush it H 2 O (solid)  H 2 O (liquid) Al (before crushing)  Al (after crushing)

Physical vs. Chemical Changes A chemical change is a change that results in one or more different substances being formed Clues that accompany a chemical change include: – A change in color of a substance – Heat released or absorbed – A solid forming For example, once again consider Iron When iron reacts with oxygen in the air, notice a color change is apparent and a new chemical is formed, rust or Iron oxide Or, consider the chemical change that occurs when you ignite your laboratory bunsen burners Notice, heat is given off and two new substances or chemicals are formed CH 4 + O 2  CO 2 + H 2 O Fe + O 2  Fe 2 O 3

What is the difference between physical and chemical changes? A physical change is the change that occurs in the physical properties of a substance without altering its chemical composition Clues that accompany a physical change include: – A change in shape – A change in state (solid, liquid, or gas) Example: Ice melting A chemical change is a change that results in one or more different substances being formed Clues that accompany a chemical change include: – A change in color – Heat released or absorbed – A solid forms Example: Iron reacts with oxygen to from rust: Fe + O 2  Fe 2 O 3

Summarize: (you can always write you own) Describe the 3 states of matter: Compare and contrast physical properties with chemical properties Besides the examples in your notes, try to come with at least two more examples of both physical and chemical properties Compare and contrast physical changes with chemical changes Besides the examples in your notes, try to come with at least two more examples of both physical and chemical changes