Physical and Chemical Properties/Changes

1Ms. Mormando's Class

Physical vs. Chemical Graphic Organizer

Ms. Mormando's Class 2

What is Matter?

Explain the physical properties of matter.

Explain the chemical properties of matter.

What is physical change?

Provide real-world examples of physical change.

What is chemical change?

Provide real-world examples of chemical change.

What is Exothermic Reaction?

What is Endothermic Reaction?

Reviewing MATTER

• Matter: anything that has mass and takes up space– Mass – the amount of matter in something

– Volume – the amount of space something occupies

• Which of the following is matter?– A car?

– A box?

– You?

Yes!

Yes!

Yes!

3Ms. Mormando's Class

What is a property?

• Property: a characteristic of a substance that can be observed

4Ms. Mormando's Class

Physical Properties

• Physical properties can be observed and measured without changing the kind of matter being studied.

• Examples:

– Melting point

– Boiling point

– Density

– Color

5Ms. Mormando's Class

Chemical Properties• Chemical Properties can be recognized only

when substances react or do not react chemically with one another; when they undergo a change in composition

• Examples:

• - Flammability

• - Reacting with Oxygen • Rusting

- Reacting with Acids

• Metals react to form compounds

• Bases react to form water and neutralize6Ms. Mormando's Class

What is a physical change?

• The chemical composition of the substance does not change

• Changes in size, shape, or state of matter

Example:

Tearing paper

7Ms. Mormando's Class

What is a chemical change?

• A change in which a new/different substance is formed

Example: burning paper

8Ms. Mormando's Class

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Chemical Changes

• Indicators of a chemical change:

•Evolution of light

•Evolution of heat

•Evolution of a gas

•Color change

•Formation of a precipitate

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Color Change

• Substance often change color during a chemical reaction.

• Example: when gray iron rusts, the product that forms is brown.

11Ms. Mormando's Class

Formation of a Precipitate• Precipitate: A solid product formed when

chemicals in two liquids react.

• Example: Seashells are formed when sea creatures release a liquid that reacts with seawater.

12Ms. Mormando's Class

Formation of a Gas

• Chemical reactions may produce a gas, like that often formed when antacid pills are mixed with excess stomach acid.

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Temperature Change

• Most chemical reactions involve temperature change

• Example: Concrete gets warmer as it hardens

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Evolution of Light

• Energy can be released in the form of light during a chemical reaction

• Example—Glow Sticks

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Endothermic and Exothermic

Reactions• Exothermic Reactions: If more energy is released when

the products form than is needed to break the bonds in the reactants then energy is released during the reaction

– Energy is released (Exit)

• Endothermic Reactions: If more energy is required to break the bonds in the reactants than is released when the product is formed then energy must be added to the reaction

– Energy is absorbed (Enter)

16Ms. Mormando's Class

Is it Physical or Chemical?

Change Physical Chemical

Melting cheese

Burning wood

Milk souring

Wadding up paper

Bicycle rusting

17Ms. Mormando's Class

Physical or Chemical Change?Tearing paper ______________

Melting ice ________________

Digesting food _____________

Rusting bicycle _____________

Chopping Wood ____________

Baking a cake ______________

Making salt water ___________

Burning wood ______________

18Ms. Mormando's Class