M1st - Matter II

Matter II

Science ‐ Middle 1st Grade St. George's College October, 2008 1

Brainstorming: How do things interact? contains

contains attracts

repulses forms positive negative

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Middle 1st Grade ‐ Matter II Name

Oral Intervention

Coin

Chocolate

Name

Marcelo

Alfredo

Antonella

Giuliana

Paulo

Joshua

Sergio

Kinley

Maria Fernanda

Arianne

Alejandro

Maria Gracia

Alejandra

Sandra

Brenda

Fiorella

Hettore

Gonzalo N.

Almendra

Rodrigo

Diego

Paolo

Anna Paula

Gonzalo R.

Gabriel

Giorgio

Sandra

Jaime

Maia

Steffano

Valeria

Bruno

Cristina

Maria Claudia

Oral Intervention

Coin

Chocolate

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Objectives • Calculate density of objects.

• Identify physical properties and describe physical changes.

• Describe how mixtures are made, and how to separate them.

• Identify different kinds of mixtures and solutions.

• Compare physical and chemical changes.

• Describe chemical reactions.

• Classify compounds as acids or bases.

• Explain how an indicator is used.

• Describe common uses of acids and bases.

Note: Most of the objectives will be covered in class, however the student must be responsible for those objectives not covered or concluded.

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Vocabulary • Physical property: a property that describes a substance by itself, such as color, shape, density, or hardness.

• Mass: the amount of matter something has.

• Volume: the amount of space something takes up.

• Density: the amount of mass something has in relation to its volume.

• Physical change: a change that does not make a substance into a new substance.

• Mixture: a combination of two or more substances that keep their original properties.

• Solution: a mixture in which all of the substances are evenly distributed.

• Suspension: a mixture that contains particles that are large enough to be seen.

• Colloid: a mixture that contains particles that are too small to see.

• Chemical change: a change in which one or more new substances are formed.

• Chemical property: a property that involves the ability of a substance to react with other materials and form new substances.

• Reactivity: the ability of a substance to go through a chemical change.

• Stability: the ability of a substance to resist going through a chemical change.

• Acid: a substance that turns blue litmus paper red.

• Base: a substance that turns red litmus paper blue.

• Indicator: a material that indicates whether a substance is an acid or a base.

• pH scale: a measure of the strength or weakness of acids and bases.

Note: Most of the vocabulary words will be covered in class, however the student must be responsible for those words not covered or concluded.

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Lesson 1: What are the Physical Properties of Matter?

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Physical Properties • Almost everything you see, touch, and smell is matter.

• Matter is anything that has mass and takes up space. But, what is matter made of?

• How can you describe matter?

• You describe matter through its physical properties. A physical property is something that describes a substance by itself and can be observed or measured without changing the identity of the substance.

Examples

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Mass, Volume and Density • Mass is the amount of matter something has, and it doesn't depend on where the thing is. It can be measured in grams or kilograms.

• Volume is the amount of space something takes up. it can be measured in liters or milliliters, pints, gallons, or cubic centimeters.

• Density is the amount of mass something has in relation to its volume. Density is equal to mass divided by volume and might be measured in grams per liter, grams per cubic centimeter, etc.

• Any substance will float on a liquid that has a higher density than it does.

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Physical Changes • When a substance undergoes a physical change, one or more of its physical properties change, but it does not become a different, it conserves its identity.

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Dissolving, Melting, and Boiling • The ability of a substance to dissolve is a physical property.. the term for this property is solubility, a measure of how much of a substance will dissolve in a liquid.

• Glass is a solid when it is cold. When you apply enough heat it softens and becomes a liquid. This property is based on melting or the change from solid to liquid.

• Boiling is the change from a liquid form to a gas form.

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Lesson 2: What are Mixtures?

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Mixtures • A Mixture is a combination of two or more substances that keep their original properties.

Mixture, or Not?

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Separating Mixtures • If the materials in a mixture keep all their original properties, it should be possible to separate them from the mixture.

• Some mixtures are easy to separate. And, remember, things in a mixture keep their original properties.

How would you separate...?

Salt and Pepper

Saltwater solution

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Solutions • All solutions are mixtures, but not all mixtures are solutions.

• A Solution is a mixture in which all the substances are evenly distributed.

• A solution results when a solute dissolves in a solvent.

• In any solution, the substance that is dissolved is called the solute, and the substance it's dissolved in is called the solvent.

• Many substances dissolve easily in water, others dissolve better in other liquids.

• Some dissolve completely and some dissolve only a little.

• Solubility is the measure of how much of a substance will dissolve in a given solvent. It is also a physical property.

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Saltwater Solution

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Other types of Mixtures • A suspension is a uniform mixture that contains particles that are large enough to be seen.

• One kind of mixture that stays mixed is a colloid. A colloid is a mixture that contains particles that are too small to see, so they never settle to the bottom. Except for the size of its particles, a colloid is exactly like a suspension.

• Another type of mixture is called an emulsion, which is a mixture of two liquids that don't dissolve.

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Solution

Mixture

Emulsion

Colloid

Suspension

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Lesson 3: What are chemical Properties of Matter?

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Chemical Properties and Changes • When a substance goes through a physical change, the substance itself is not changed.

• A chemical change is a change in which one or more new substances are formed.

• One way to observe if a chemical reaction has happened is to observe for new chemical properties. A chemical property is something that describes the ability of a substance to react with other materials and form new substances.

• Reactivity is the ability of a substance to go through a chemical change.

• The opposite of reactivity is stability. Stability is the ability of a substance to resist going through a chemical change.

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Types of Reactions • There are millions of possible chemical reactions, but all of them can fit onto one of four categories:

Synthesis Reaction Synthesis means "putting together". In a synthesis reaction, two or more substances are put together to form a single substance.

Carbon + Oxygen

Carbon dioxide

Decomposition Reaction Decomposition means "breaking up". In a decomposition reaction, a single substance breaks up, forming two or more different substances.

Water

Hydrogen + Oxygen

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Types of Reactions Single Displacement Reaction In a single displacement reaction, one substance replaces another.

Magnesium + Lead nitrate

Lead + Magnesium nitrate

Double Displacement Reaction In a double displacement reaction, two substances switch places.

Sodium chloride + Silver nitrate

Sodium nitrate + Silver Chloride

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Preventing Chemical Changes • Heat can start or speed up a chemical reaction.

• The spoiling of food is a chemical reaction. Putting food into a refrigerator slows this reaction, freezing it slows it even more.

That's why food stays better and longer in the freezer than in the refrigerator.

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Lesson 4: What are Acids and Bases?

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Acids and Bases • An acid is a substance that turns blue indicator paper into red.

Acids are compounds that donates protons [H+] in solution.

• A base is a substance that turns red indicator paper into blue.

• An important property of acids and bases is that they react together to form water and an additional substance, in a reaction called Neutralization.

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Indicators • Indicators are substances or objects that indicate if a substance is an acid or a base.

• The pH scale is a measure of the strength or weakness of acids and bases.

• the pH scale ranges from 0 to 14. Neutral is right in the middle, at 7. That means it is neither an acid nor a base.

• The pH of acids ranges from 7 to 0. the lower pH value, the stronger the acid is.

• The pH of bases ranges from 7 to 14. the higher the pH value, the stronger the base is.

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