Chapter: Matter and Its Changes Table of Contents Section 1: Physical Properties and Changes

Physical properties of an object color, shape Length, mass, volume, density State of matter – solid, liquid, gas Melting and Boiling Points Metallic properties magnetic, malleability, and ductility

Observing involves seeing, hearing, tasting, touching, and smelling. Any characteristic of a material that can be observed or measured without changing the identity of the material is a physical property. Using Your Senses Physical Properties and Changes 1 1

The detergent bottles shown are made plastic regardless of the differences in the physical properties of color or shape. Physical Properties— Color and Shape Physical Properties and Changes 1 1

One useful and measurable physical property is length. Length and Mass Physical Properties and Changes 1 1 Length is measured using a ruler, meterstick, or tape measure. Objects can be classified by their length.

Mass is a physical property that describes the amount of material in an object. Length and Mass Physical Properties and Changes 1 1 For example, two boxes of the same detergent may have different masses. One box may be heavier than the other but the formula of the detergent in each box is the same.

Volume measures the amount of space an object takes up. Volume and Density Physical Properties and Changes 1 1 Liquids usually are measured by volume.

Matter is anything that has mass and takes up space. In a physical change, the physical properties of a substance change, but not what it is (the identity) A piece of clay weather red or blue is still clay Physical Properties and Changes 1 1 Physical Properties— Color and Shape

Another measurable physical property related to mass and volume is density—the amount of mass a material has in a given volume. Volume and Density Physical Properties and Changes 1 1 Density is found by dividing the mass of an object by its volume. density = mass/volume, or D = m/V

These balls take up about the same space, but the bowling ball has more mass than the other ball. Same Volume, Different Mass Physical Properties and Changes 1 1 Therefore, the bowling ball is more dense.

Density energy Related to state of matter of a material gas liquid solid

Heat = energy Things need more space as they get more energy

Does a substance have more space between its molecules because it has more energy Or does it have more energy because it has more space between its molecules

The density of a material stays the same as long as pressure and temperature stay the same. Same Volume, Different Mass Physical Properties and Changes 1 1 Water at room temperature has a density of 1.00 g/cm 3. When you do change the temperature or pressure, the density of a material can change.

The four states of matter are solid, liquid, gas and plasma (PLAZ muh). States of Matter Physical Properties and Changes 1 1 The state of matter of a substance depends on its temperature and pressure. Click image to view movie.

States of Matter Physical Properties and Changes 1 1 The state of matter of a material is a physical property.

The plasma state occurs at very high temperatures and is found in fluorescent (floo RE sunt) lightbulbs, the atmosphere, and in lightning strikes. States of Matter Physical Properties and Changes 1 1 The state of matter of a material is another physical property.

Objective: Chemical Reactions

Objective: Understanding States of Matter

Physical Properties and Changes The material stays the same 1. color and shape a.making a ball of clay into a cube of clay b.Painting a chair red

Physical Properties and Changes The material stays the same 1. color and shape a.making a ball of clay into a log of clay b.Painting a chair red 2. Length and mass a. if cut or decreased in size – only a physical change still is the same material cutting a carrot ino smaller chunks

Physical Properties and Changes The material stays the same 1. color and shape a.making a ball of clay into a log of clay b.Painting a chair red 2. Length and mass a. if cut or decreased in size – only a physical change still is the same material cutting a carrot ino smaller chunks 3. Density – a physical quality involving mass and volume is a characteristic to identify a material A material’s density can change by changing room temp or pressure but it remains the same material

States of Matter Energy Levels HighestMiddleLowest GasLiquidSolid Energy Level Increasing Increasing heat will cause lead to increased kinetic energy. Increasing heat causes decreased density, increases volume but keeping the amount of mass the same. Higher energy causes greater motion of the molecules and so they spread apart

Physical properties of States of Matter Definite volumeDefinite shape of container SolidYes

Physical properties of States of Matter Definite volumeDefinite shape of container SolidYes LiquidYesNo

Physical Properties of States of Matter Definite volumeDefinite shape of container SolidYes LiquidYesNo Gas No – will take volume of container it is in no

Melting and Boiling Points Melting point – a solid becomes a liquid Boiling point – a liquid becomes a gas Melting and boiling points are physical properties used to identify (classify) materials Every pure material has a boiling and melting point of its own MaterialMeltBoil water32 F ( 0 C)212 F (100 C) nitrogen C Lead327.5 C

Properties of Metals Luster- the shiny nature of the material Such as a new penny or coin Malleability – to be shaped by hammering Shaping a sword by hammering on an anvil Ductility – ability to be pulled into a wire Magnetic – ability to be attracted to a magnet

Matter is made up of moving particles. Moving Particles Physical Properties and Changes 1 1 The particles of a solid vibrate in a fixed position. They remain close together and give the solid a definite shape and volume.

The particles of a liquid are moving much faster and have enough energy to slide past on another. Moving Particles Physical Properties and Changes 1 1 This allows a liquid to take the shape of its container.

Gas particles of a are moving so quickly that they have enough energy to move freely away from other particles and will spread out to fill any container. Moving Particles Physical Properties and Changes 1 1

Hot air cold air Which direction, why?

You witness a change of state when you place ice cubes in a cup and they melt. Changes of State Physical Properties and Changes 1 1 You still have water but in another form. The opposite physical change happens when you put liquid water in ice-cube trays and pop them in your freezer.

The temperature at which a solid becomes a liquid is its melting point. Melting and Boiling Points Physical Properties and Changes 1 1 The melting point of a pure substance does not change with the amount of the substance.

When a substance melts, it changes from a solid to a liquid. Melting and Boiling Points Physical Properties and Changes 1 1 This is a physical change, and the melting point is a physical property.

The boiling point is the temperature at which a liquid becomes a gas. Melting and Boiling Points Physical Properties and Changes 1 1

Melting and Boiling Points Physical Properties and Changes 1 1 Each pure substance has a unique boiling point. The boiling point of water is 100°C

The boiling and melting point can help to identify a substance. Melting and Boiling Points Physical Properties and Changes 1 1 If you know the boiling points and melting points of substances, you can classify substances based on those properties.

“A2” heated more Same mass “A” “B” “A1 heated” Same mass “B” Room temp “B” Room temp Same mass

A A A1A1 A2A2 If their state of matter wasn’t changed, what happened?

A A A1A1 A2A2 If their state of matter was changed, name them

As you heat a material and compare it to the same unheated material the density of the heated material will decrease as the molecules spread and the volume increases.

You can classify things as solids, liquids or gases or according to color, shape, length, mass, volume or density. Metallic Properties Physical Properties and Changes 1 1 What properties do metals have?

Metals - a shiny appearance. How do metals look? Physical Properties and Changes 1 1 This shine is called luster. Words to describe the appearance of nonmetallic objects are pearly, milky, or dull.

Many metals can be hammered, pressed or rolled into thin sheets. Uses of Metals Physical Properties and Changes 1 1 This property of metals is called malleability

Many metals can be drawn into wires = ductility Uses of Metals Physical Properties and Changes 1 1

Some metals respond to magnets. Uses of Metals Physical Properties and Changes 1 1 Some metals have groups of atoms that can be affected by the force of a magnet, and they are attracted to the magnet because of that force.

Physical properties—such as appearance, state, shape, length, mass, volume, ability to attract a magnet, density, melting point, boiling point, malleability, and ductility can be used to help you identify, separate, and classify substances. Using Physical Properties Physical Properties and Changes 1 1

When you do laundry, you sort according to physical properties. Perhaps you sort by color. Sorting and Separating Physical Properties and Changes 1 1 What are some things you may sort? Think of trick or treat

Scientists who work with animals use physical properties or characteristics to determine the identity of a specimen. Sorting and Separating Physical Properties and Changes 1 1 They do this by using a tool called a dichotomous key.

To begin the identification of you unknown animal, you are given two choices. Sorting and Separating Physical Properties and Changes 1 1 Your animal will match only one of the choices. Based on your answer, you are either directed to another set of choices or given the name of the specimen you are identifying.

Sorting and Separating Physical Properties and Changes 1 1 All things Is it alive yes no Human, mouse, grasshopper, etc Car, button, chalk Can it talk yes no

Sorting and Separating Physical Properties and Changes 1 1 All things Is it alive yes no Human, mouse, grasshopper, etc Car, button, chalk Can it talk yes no

Often, determining the identity of something that is unknown is easiest by using the process of elimination. Narrowing the Options Physical Properties and Changes 1 1 Scientists use similar methods to determine the identities of living and nonliving things.

Label and describe the energy of the particles In each state of matter

Chapter: Matter and Its Changes Table of Contents Section 2: Chemical Properties and ChangesChemical Properties and Changes

Chemical properties: 1.Ability to burn wood catches fire 1.React with oxygen or sulfur iron forms rust, silver tarnishes 2.React with heat or light fading of ink, fabric 3.Break down by electricity water becomes hydrogen and oxygen

Signs of chemical change: 1. new material formed 2. bubbles 3. production of heat, light, smoke 4. change in color such as fading 5. production of sound

Chemical propertyChemical change The ability to do something What happened flammabilityWord burned React with oxygenNail rusted React with lightCurtain faded React to electric currentWater breaks down to oxygen and hydrogen

Watch the demo in the bottle Draw and label picture 1. before 2. after (during) What do you see? What is this a sign of?

Examine the brush (car) What do you notice? Name the product? How did it happen? What is the property? What kind of change is this?

Chemical Properties and Changes 4. Changes when electricity goes thru it producing new materials 1.Flammability (burns) producing new materials 3. Changes when exposed to heat or light producing new materials 2. Reacts with other chemicals producing new materials

Signs of a Chemical Change Chemical Properties and Changes Bubbles are a sign that a chemical change has taken place. Other signs of a chemical change include: the production of: a new material (a solid (powder), liquid, or gas),, smoke, light, heat, change in color, or sound.

Ability to Change Some properties do indicate a change of identity for the substances involved. A chemical property is a characteristic that gives a substance the ability to undergo a change. (Flammability is a chemical property) Chemical Properties and Changes 2 2 It results in a new substance.

Common Chemical Properties A chemical change is a change in the identity of a substance. A change has occurred in the chemical properties of that substance. (paper burns to ashes – it is no longer paper, its properties have changed) A new substance or substances are formed as a result of such a change. Chemical Properties and Changes 2 2

The Law of Conservation of Mass The law of conservation of mass states that the mass of what you end with is always the same as the mass of what you start with. Chemical Properties and Changes When something is burned the ashes remain but the rest of the mass is changed to gases and smoke Oxygen + Log = other gases + ashes + smoke MASS before = MASS after Mass is not created or destroyed

Classify According to Chemical Properties Chemical Properties and Changes 2 2 Physical properties of a substance are easily observed, but the chemical properties can’t be observed without changing the substance.

Classifying by to Chemical Properties Chemical Properties and Changes Properties

Ability to Change Chemical property a characteristic that gives a substance the ability to change and results in a new substance. Chemical Properties and Changes 2 2

Common Chemical Properties A chemical change is a change in the identity of a substance because of the due to the chemical properties of the new substance. It causes a new substance or substances to form as a result of the change. Chemical Properties and Changes 2 2 Burn wood you get charcoal Expose an apple or banana to air the dark material is a new substance

Common Chemical Properties Wood can burn. This chemical property is called flammability. Chemical Properties and Changes 2 2 What results from burning wood?

Common Chemical Properties 1.Flammability – the ability to burn. 2.Reacting with other chemicals a. iron reacts with oxygen – rust forms (corrosion) iron oxide b. copper reacts with oxygen turn green c. silver turns black – it reacts sulfur in air or sweat Chemical Properties and Changes 2 2

Common Reactions An unpainted iron gate will rust in time. The rust is a result of oxygen in the air reacting with the iron and causing corrosion. Chemical Properties and Changes 2 2 rust is a new substance called iron oxide,

Common Reactions Tarnish develops on silver when it reacts with sulfur in the air. Chemical Properties and Changes 2 2 The ability to react with different chemicals is a chemical property. Iron – to oxygen Copper – to oxygen Silver – to sulfur

Heat and Light Many vitamins will change when exposed to light, curtains when exposed to the sun Chemical Properties and Changes 2 2 This is a chemical property. They are protected in colored bottles from undergoing a chemical change with light.

Heat and Light Some substances are sensitive to heat or cooling. They will undergo a chemical change only when heated or cooled. Chemical Properties and Changes 2 2 One example is limestone. If limestone is heated, it goes through a chemical change and produces carbon dioxide and lime.

Heat and Light Another chemical property is the ability to change with electrical contact. Chemical Properties and Changes 2 2 Electricity can cause a change in some substances and decompose (break down) some compounds. Water is one compound that can be broken down with electricity. It forms hydrogen and oxygen

Ability to change with electrical contact. Chemical Properties and Changes Electricity can cause a change in some substances and decompose ( break down to components it is made of) some compounds. Water is one compound that can be broken down with electricity. 4. Change when electricity is put thru it

Something New The important differences in a chemical change in that a new substance is formed. Chemical Properties and Changes 2 2 If eggs, sugar, flour, and other ingredients didn’t change chemically through baking, you couldn’t enjoy birthday cake. Cake begins as liquid and ends as solid. The baked cake clearly has different physical and chemical properties.

Signs of Change Chemical Properties and Changes 2 2 Bubbles are a sign that a chemical change has taken place. Other signs of a chemical change include: the production of heat, light, smoke, change in color, and sound.

Is it reversible? Chemical changes can’t be reversed using physical means. Chemical Properties and Changes 2 2 For example, the ashes in a fireplace cannot be put back together to make the logs that you had to start with.

Classify According to Chemical Properties The physical properties of a substance are easily observed, but the chemical properties can’t be observed without changing the substance. Chemical Properties and Changes 2 2

Classify According to Chemical Properties Chemical Properties and Changes 2 2 However, once you know the chemical properties, you can classify and identify matter based on those properties.

Classify According to Chemical Properties For example, if you try to burn what looks like a piece of wood but find that it won’t burn, you can rule out that it is wood Chemical Properties and Changes 2 2 All matter Can it burn Not wood May be wood

The Law of Conservation of Mass The law of conservation of mass states that the mass of what you end with is always the same as the mass of what you start with. Chemical Properties and Changes 2 2 He determined that a fire does not make mass disappear or truly get rid of anything.

Where did the mass go? When flammable materials burn, they combine with oxygen. Ash, smoke, and gases are produced. Chemical Properties and Changes 2 2 The smoke and gases escape into the air.

Where did the mass go? If you could measure the mass of the oxygen and all of the original firewood that was burned and compare it to the remaining mass of the ash, smoke, and gas, they would be equal. Chemical Properties and Changes 2 2 Mass is not destroyed or created during any chemical change.