Science Ch 2-4 Notes

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Table sugar is a compound made of carbon, hydrogen, and oxygen. If sugar contains 41.86% carbon and 6.98% hydrogen, what percentage of sugar is oxygen?

51.16% (100% - 41.86% - 6.98%)

When scientists record a gas's volume, they also record its temperature and pressure. Why?

Because of each are directly related.

What is dry ice made of?

Carbon Dioxide

Removing energy will cause the particles to begin locking into place. Freezing is an exothermic (EK so THUHR mik) change because energy is removed from the substance as it changes state. Freezing is an ________ change because energy is removed.

Exothermic (ex = exit or remove)

What are the properties of a Nonmetal?

Nonmetals make up the second category of elements. They do not conduct heat or electric current, and solid nonmetals are dull in appearance. Solids tend to be brittle. you cannot hammer.

Your friend tells you that a shiny element has to be a metal. Do you agree? Explain.

Not necessarily. It could be a metalloid.

Describe how the motion and arrangement of particles in a substance change as the substance freezes.

Particle move more slowly and energy is removed, causing the substance to form a solid

Identify the state of matter shown in the jar where the particles are close together.

Solid state of matter

The solute is dissolved into ________

Solvent

Another important property of liquids is viscosity. Viscosity is a liquid's resistance to flow. Usually, the stronger the attractions between the molecules of a liquid, the more viscous the liquid is. For example, honey flows more slowly than water. So, honey has a higher viscosity than water. What is viscosity?

The resistance of a gas or liquid to flow

What is viscosity?

The resistance of a gas or liquid to flow

What substance is dissolved in solutions?

The solute is the substance that is dissolved

What is melting?

the change of state in which a solid becomes a liquid by adding heat

What is Boiling?

the conversion of a liquid to a vapor when the vapor pressure of the liquid equals the atmospheric pressure

What is states of matter?

the physical forms of matter, which include solid, liquid, and gas

What is gas?

A form of matter that does not have a definite volume or shape

Comparing Physical and Chemical Changes

A physical change is a change of matter from one form to another without a change in chemical properties. A chemical change is a change that occurs when one or more substances change into entirely new substances with different properties.

Explain why an element is a pure substance.

Because the element contains only one type of particle. These particles are called atoms.

What are atoms generated from?

From pure substance - only one type of particles.

Solutions A solution is a mixture that appears to be a single substance. A solution is composed of particles of two or more substances that are distributed evenly among each other. Solutions have the same appearance and properties throughout the mixture. What is are solutions?

Is composed of particles of two or more substances that are distributed evenly among each other, that appears to be a single substance.

Iron is a solid, gray metal. Oxygen is a colorless gas. When they chemically combine, rust is made. Rust has a reddish brown color. Why is rust different from the iron and oxygen that it is made of?

It's color is different and its properties are different because its particles are different

No Chemical Changes in a Mixture No chemical change happens when a mixture is made. So, each substance in a mixture has the same chemical makeup it had before the mixture formed. That is, each substance in a mixture keeps its identity. Why do substances in a mixture keep their identities?

No chemical change happens when a mixture is made.

Does physical change form new substances? Why or Why not?

No, because the physical property is still the same. Ex: a silver spoon pounded into a silver heart is still silver.

A jar contains samples of the elements carbon and oxygen. Does the jar contain a compound? Explain your answer.

Only if there is a correct ratio of the elements to form a compound

Describe the movement of the particles in a liquid.

The particles in liquids move fast enough to overcome some of the attractions between them. The particles slide past each other until the liquid takes the shape of its container.

What are the properties of a metal?

Metals are shiny, and they conduct heat energy and electric current. They can be hammered into thin sheets and can be drawn into thin wires

Which category of elements would you choose to make a container that wouldn't shatter if dropped? Explain

Metals. They are are hard.

What is the mass often expressed as?

Milligrams (mg)

The Ratio of Components in a Mixture A compound is made of elements in a specific mass ratio. However, the components of a mixture do not need to be mixed in a definite ratio. Does the compound of a mixture have to have an exact ratio?

No

Elements are pure substances. A pure substance is a substance in which there is only one type of particle. So, each element contains only one type of particle. These particles, called atoms, are much too small for us to see. For example, every atom in a 5 g nugget of the element gold is like every other atom of gold. The particles of a pure substance are alike no matter where they are found Can elements be broken down? Why or why not?

No an element cannot be broken down, because it is a pure substance, where there is only one type of particle.

Would using dry ice in your holiday punch cause it to become watery after several hours? Why or why not?

No because dry ice does not melt to a liquid it would go through sublimation and melt into a gas directly.

There are six liquids in the graduated cylinder. Each liquid has a different density. If the liquids are carefully poured into the cylinder, they can form six layers because of the differences in density. The densest layer is on the bottom. The least dense layer is on top. If six different liquids in a cylinder, each one one step denser than the other from 1-6, 6 being the densest. Which layer of liquid would be at the bottom of the cylinder?

The liquid with a density level of 6 as it would be the densest.

Discuss how the particles in the jar of liquid are attracted to each other.

The particles move fast enough to overcome some of the attraction between them. The particles are close together but can slide past one another.

What are the effects of a warm temperature on gas particles?

The particles move faster, using less gas

The process in which particles of substances separate and spread evenly throughout a mixture is known as dissolving. In solutions, the solute is the substance that is dissolved. The solvent is the substance in which the solute is dissolved. A solute must be soluble, or able to dissolve, in the solvent. A substance that is insoluble, or unable to dissolve, forms a mixture that is not a solution. What is dissolving in a mixture?

The process in which particles of substances separate and spread evenly

What is Condensation?

the change of state from a gas to a liquid

What is Evaporation?

the change of state from a liquid to a gas

What is Sublimation?

the process in which a solid changes directly into a gas

What is density?

the ratio of the mass of a substance to the volume of the substance

What is solid?

The state of matter in which the volume and shape of a substance are fixed

What is liquid?

The state of matter that has a definite volume but not a definite shape

What is the melting point of a substance?

The temperature at which a substance changes from a solid to a liquid.

What happens to the pressure of a gas if the volume of gas is tripled at a constant temperature?

The volume decreases.

Which of the following is a characteristic property? a. density b. chemical reactivity c. solubility in water d. All of the above

a. density

The change of state from a liquid to a solid is called freezing. The temperature at which a liquid changes into a solid is the liquid's freezing point. Freezing is the reverse process of melting. Thus, freezing and melting occur at the same temperature. If energy is added at 0 degrees Celsius, ice will melt. If energy is removed at 0 degrees Celsius, ice will freeze. What degree will ice freeze? Will ice melt?

0 degree Celsius. It depends on the energy added or removed. If added it will melt, if removed, it will freeze.

What degree does boiling begin?

100 degrees Celsius

Is evaporation a physical or a chemical change?

A physical change,

A compound is a pure substance composed of two or more elements that are chemically combined. Elements combine by reacting, or undergoing a chemical change, with one another. A particle of a compound is a molecule. Molecules of compounds are formed when atoms of two or more elements join together. What is a compound?

A pure substance composed of two or more elements that are chemically combined to form a new pure substance. Elements combine by reacting, or undergoing a chemical change, with one another.

What is an element?

A pure substance that cannot be separated into simpler substances by physical or chemical means

Use the following terms in the same sentence: element and pure substance.

An element is considered to be a pure substance because it has only one type of particle and cannot be broken down any further

Methods of Breaking Down Compounds The only way to break down a compound is through a chemical change. Sometimes, energy is needed for a chemical change to happen. Two ways to add energy to break down a compound are to apply heat and to apply an electric current. What two ways to add energy to break down compounds?

Apply Heat Apply electric current

When most substances lose or gain energy, one of two things happens to the substance: its temperature changes or its state changes. The temperature of a substance is related to the speed of the substance's particles. So, when the temperature of a substance changes, the speed of the particles also changes. But the temperature of a substance does not change until the change of state is complete. For example, the temperature of boiling water stays at 100°C until it has all evaporated. Explain the relationship between the particles of a substance and the temperature of a substance as it changes state.

As the temperature increase the particles move with more speed. As the temperature decreases, the particles move slower.

Adding energy to a solid increases the temperature of the solid. As the temperature increases, the particles of the solid move faster. When a certain temperature is reached, the solid will melt. The temperature at which a substance changes from a solid to a liquid is the melting point of the substance. Why would a solid melt?

Because the temperature rises causing the particles to move faster EX: Holding ice in your hand. The increase in temperature causes the ice to melt

Boiling is the change of a liquid to a vapor, or gas, throughout the liquid. Boiling occurs when the pressure inside the bubbles, which is called vapor pressure, equals the outside pressure on the bubbles, or atmospheric pressure. The temperature at which a liquid boils is called its boiling point. No matter how much of a substance is present, neither the boiling point nor the melting point of a substance change. What happens when boiling occurs?

Boiling occurs when the pressure inside the bubbles, which is called vapor pressure, equals the outside pressure on the bubbles, or atmospheric pressure.

Evaporation (ee VAP uh RAY shuhn) is the change of a substance from a liquid to a gas. Evaporation can occur at the surface of a liquid that is below its boiling point. For example, when you sweat, your body is cooled through evaporation. Your sweat is mostly water. Water absorbs energy from your skin as the water evaporates. You feel cooler because your body transfers energy to the water. Evaporation also explains why water in a glass on a table disappears after several days. Adding energy to a liquid substance causes the liquid to ____.

Change to gas.

What type of change is needed to break down a compound?

Chemical Change

In your own words, write a definition for the term compound.

Compound: two elements that combine to make a new pure substance that can be broken down into simpler compounds.

Breaking Down Compounds Some compounds can be broken down into their elements by chemical changes. Other compounds break down to form simpler compounds instead of elements. Compounds can be broken down into what two types of substances?

Elements Simpler compounds

For a solid to change directly into a gas, the particles of the substance must move from being very tightly packed to being spread far apart. So, the attractions between the particles must be completely overcome. The substance must gain energy for the particles to overcome their attractions. Thus, sublimation is an endothermic change because energy is gained by the substance as it changes state. What type of change is Sublimation?

Endothermic - adding energy to create a tightly packed substance.

The temperature of water in a beaker is 25°C. After adding a piece of magnesium to the water, the temperature increases to 28°C. Is this an exothermic or endothermic reaction?

Endothermic - by adding the piece of magnesium, energy is added raising the temperature and causing the particles to move faster.

How are evaporation and boiling different? How are they similar?

Evaporation can occur at the surface of a liquid that is below its boiling point. Boiling occurs when the pressure inside the bubbles, which is called vapor pressure, equals the outside pressure on the bubbles, or atmospheric pressure. They both change of state from a liquid to a gas

There are three categories of elements. Name them.

Metals Nonmetal Metalloids

What are the five Changes of State?

Melting Evaporation Boiling Condensation Sublimation

Compounds in Industry The compounds found in nature are not usually the raw materials needed by industry. Often, these compounds must be broken down to provide elements or other compounds that can be used as raw material. For example, aluminum is used in cans and airplanes. But aluminum is not found alone in nature. Aluminum is produced by breaking down the compound aluminum oxide. Ammonia is another important compound used in industry. It is used to make fertilizers. Ammonia is made by combining the elements nitrogen and hydrogen. Are raw materials usually found in nature when an industry needs an element or compound? Explain.

No raw materials are not usually found in nature. Typically Industries will need to break down the compound to form an element. EX: Fertilizer is made with Ammonia by combining the elements nitrogen and hydrogen.

A molecule is a __________ .

Particle of a compound.

Properties of Elements Each element can be identified by its unique set of properties. For example, each element has its own characteristic properties. These properties do not depend on the amount of the element present. Characteristic properties include some physical properties, such as boiling point, melting point, and density. Chemical properties, such as reactivity with acid, are also characteristic properties. Characteristic properties include _______

Physical Properties - Boiling Point, Melting Point, and Density Chemical Properties - reactivity with acid

All changes of state are _________.

Physical changes

Solid crystals of iodine were placed in a flask. The top of the flask was covered with aluminum foil. The flask was gently heated. Soon, the flask was filled with a reddish gas. What change of state took place? Explain your answer.

Sublimation, because it changes from a solid directly to gas.

Explain what happens to the temperature of an ice cube as it melts

Temperature rises, energy is added, causing the particle to move faster and melt into liquid.

Hiking on a high mountain, would the boiling point increase or decrease?

The boiling point would decrease. The higher you are above sea level, the boiling point would go lower than 100 degrees Celsius.

A change of state is the change of a substance from one physical form to another. All changes of state are physical changes. In a physical change, the identity of a substance does not change. What is a change of state?

The change of a substance from one physical form to another. EX: Freezing ice cube to melted water. Evaporation to Condensation

The Ratio of Elements in a Compound Elements do not randomly join to form compounds. Elements join in a specific ratio according to their masses to form a compound. For example, the ratio of the mass of hydrogen to the mass of oxygen in water is 1 to 8. This mass ratio can be written as 1:8. This ratio is always the same. Every sample of water has a 1:8 mass ratio of hydrogen to oxygen. What happens if a sample of a compound has a different mass ratio of hydrogen to oxygen?

The compound cannot be water.

Separating Mixtures Through Physical Methods You don't like mushrooms on your pizza? Just pick them off. This change is a physical change of the mixture. The identities of the substances do not change. But not all mixtures are as easy to separate as a pizza. You cannot just pick salt out of a saltwater mixture. One way to separate the salt from the water is to heat the mixture until the water evaporates What happens when heat is added to saltwater?

The water evaporates separating the mixture of saltwater.

An element may share a property with another element, but other properties can help you tell the elements apart. What does this mean?

This means that even though elements may have the same or similar properties. Each one will have it's own property that will set them apart.

The particles of a substance move differently depending on the state of the substance. The particles also have different amounts of energy when the substance is in different states. For example, particles in liquid water have more energy than particles in ice. But particles of steam have more energy than particles in liquid water. So, to change a substance from one state to another, you must add or remove energy. Why would you add or remove energy from a particle?

To change from one substance to another. EX: add more energy to liquid water and it becomes steam

How are molecules formed?

When atoms of two or more elements join together.

Does the temperature of boiling water remain the same during evaporation?

Yes, the temperature of boiling water stays at 100°C until it has all evaporated.

Properties: Compounds Versus Elements A compound has properties that differ from those of the elements that form it. Sodium chloride, or table salt, is made of two very dangerous elements—sodium and chlorine. Sodium reacts violently with water. Chlorine is a poisonous gas. But when combined, these elements form a harmless compound with unique properties. Sodium chloride is safe to eat. It also dissolves (without exploding!) in water. Can you combine two or more very dangerous elements to form a harmless compound?

Yes. some elements are very dangerous by themselves, however, you can combine them and form an element that is not dangerous at all

Properties of Mixtures All mixtures—even pizza—share certain properties. A mixture is a combination of two or more substances that are not chemically combined. When two or more materials are put together, they form a mixture if they do not react to form a compound. For example, cheese and tomato sauce do not react when they are used to make a pizza. So, a pizza is a mixture. What is a mixture?

a combination of two or more substances that are not chemically combined

An element is a pure substance that cannot be separated into simpler substances by physical or chemical means. What is an element?

a pure substance that cannot be separated into simpler substances by physical or chemical means.

Dry ice is carbon dioxide in a solid state. It is called dry ice because instead of melting into a liquid, it goes through sublimation. Sublimation is the change of state in which a solid changes directly into a gas. Dry ice is much colder than ice made from water. Sublimation changes _______________.

a solid directly into a gas.

A pure substance is a substance in which there is only one type of particle. So, each element contains only one type of particle. These particles, called atoms, are much too small for us to see. For example, every atom in a 5 g nugget of the element gold is like every other atom of gold. The particles of a pure substance are alike no matter where they are found What is a pure substance?

a substance in which there is only one type of particle

A Metalloid a. may conduct electric current. b. can be ductile. c. is also called a semiconductor. d. All of the above

d. All of the above

The elements in a compound a. join in a specific ratio according to their masses. b. combine by reacting with one another. c. can be separated by chemical changes. d. All of the above

d. All of the above

The change from a solid directly to a gas is called a. evaporation. b. boiling. c. melting. d. sublimation.

d. sublimation.

Melting is an endothermic (EN doh THUHR mik) change because energy is gained by the substance as it changes state. When an ice cream cone begin to melt in the summer, what type of change is that?

endothermic (EN doh THUHR mik) change - (endo = enter or add)

Condensation is the change of state from a gas to a liquid. Condensation and evaporation are the reverse of each other. The condensation point of a substance is the temperature at which the gas becomes a liquid. And the condensation point is the same temperature as the boiling point at a given pressure. For a gas to become a liquid, large numbers of particles must clump together. Particles clump together when the attraction between them overcomes their motion. For this to happen, energy must be removed from the gas to slow the movement of the particles. Because energy is removed, condensation is an exothermic change. Condensation becomes a liquid when _____ is removed. What type of change is Condensation?

energy removed Condensation is an exothermic change (exit or removed)

What are the properties of a metalloid?

have properties of both metals and nonmetals. Also called semiconductors. Some are shiny, some are dull. Some what able to be hammered. Some are good conductors and some are poor conductors.

Properties of Compounds As an element does, each compound has its own physical properties. Physical properties include melting point, density, and color. Compounds can also be identified by their different chemical properties. Some compounds react with acid. For example, calcium carbonate, found in chalk, reacts with acid. Other compounds, such as hydrogen peroxide, react when exposed to light. What are three physical properties used to identify compounds?

melting point, density, and color

In fact, water boils at 100°C only at sea level, because of atmospheric pressure. Atmospheric pressure is caused by the weight of the gases that make up the atmosphere. Atmospheric pressure varies depending on where you are in relation to sea level. Atmospheric pressure is lower at higher elevations. The higher you go above sea level, the fewer air particles there are above you. So, the atmospheric pressure is lower. Imagine boiling water at the top of a mountain. The boiling point would be lower than 100°C. For example, Denver, Colorado, is 1.6 km above sea level. In Denver, water boils at about 95°C. What is Atmosphere pressure?

the weight of the gases that make up the atmosphere.

Matter and Chemical Changes Chemical changes change the identity of the matter involved. So, most of the chemical changes that occur in your daily life, such as a cake baking, would be hard to reverse. Imagine trying to unbake a cake. However, some chemical changes can be reversed by more chemical changes. For example, the water formed in the space shuttle's rockets could be split into hydrogen and oxygen by using an electric current.

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What happens to the volume of a balloon that is taken outside on a cold winter day? Explain.

Because it is colder, the particles would move slower, causing more volume of gas to be used.

In your own words, write a definition for each of the following terms: mass, weight, and inertia.

Mass:how much matter is inside of the object. Weight: how much the gravitational force is on an object. Inertia: an object won't just stop moving, inertia keeps it going until its slow and stops

Explain the relationship between mass and inertia.

Something that has more mass is harder to get moving and has greater inertia.

Measuring Mass and Weight A brick and a sponge have the same volume. But because the brick has more mass, a greater gravitational force is exerted on the brick than on the sponge. As a result, the brick weighs more than the sponge. Which has more gravitational force a sponge or a brick?

The brick and the sponge take up the same amount of space. But the brick has more matter in it, so its mass—and thus its weight—is greater.

What is surface tension?

The force that acts on the surface of a liquid and that tends to minimize the area of the surface

Describe what happens to a substance when it goes through a physical change.

The shape may change, but the properties of the item does not.

Volume of an Irregularly Shaped Solid Object - pge 40

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Compare high pressure to low pressure.

A basketball has higher pressure, because there are more particles of gases in it, and they are closer together. The particles collide inside the ball at a faster rate. A beach ball has a lower pressure because there are fewer particles of gas, and they are farther apart. The particles in the beach ball collide with the inside of the ball at a slower rate.

What is Boyles Law?

States that the volume of a fixed mass of gas varies inversely with pressure at constant temperature. As the volume increases, the pressure decreases. As the volume decreases, the pressure increases.

Particles of gas __________

move fast enough to overcome almost all of the attraction between them. The particles are far apart and move independently of one another.

Identify six examples of physical properties.

1. Thermal conductivity 2. Slate 3. Density 4. Solubility 5. Ductility 6. Malleability

Scientists found that the temperature, pressure, and volume of a gas are linked. Changing one of the factors changes the other two factors. The relationships between temperature, pressure, and volume are described by gas laws. What are the two laws of Gas behaviors?

Boyles Law Charles's law

What are some examples of physical changes?

Freezing water to make ice cubes sanding a piece of wood Melting butter for popcorn

Describe gas behaviors

Gases behave differently from solids or liquids. Unlike the particles that make up solids and liquids, gas particles have a large amount of empty space between them. The space that gas particles occupy is the gas's volume, which can change because of temperature and pressure.

Would you believe that one small tank of helium can fill almost 700 balloons? How is this possible? After all, the volume of a tank is equal to the volume of only about five filled balloons. The answer has to do with helium's state of matter. How is this possible?

Helium is a gas. Gas is the state of matter that has no definite shape or volume. The particles of a gas move quickly. So, they can break away completely from one another. There is less attraction between particles of a gas than between particles of the same substance in the solid or liquid state.

Would an elephant weigh more or less on the moon than it would weigh on Earth? Explain your answer.

Less ,since the moon has less gravity than Earth.

Another chemical property is reactivity. Reactivity is the ability of two or more substances to combine and form one or more new substances. What does the term reactivity mean?

Reactivity is the ability of two or more substances to combine and form one or more new substances. Ex: When Iron is exposed to oxygen it rust

The volume of a gas can change, but the volume of a solid cannot. Explain why this is true.

Solids do not move fast enough to over-come the strong attraction between them. Gas is the state of matter that has no definite shape or volume. The particles of a gas move quickly. So, they can break away completely from one another.

You see chemical changes more often than you may think. For example, a chemical reaction happens every time a battery is used. Chemicals failing to react results in a dead battery. Chemical changes also take place within your body when the food you eat is digested. What are some examples of chemical changes?

Sour milk smells bad because bacteria forms a new substance in the milk.

You have 3 L of gas at a certain temperature and pressure. What would the volume of the gas be if the temperature doubled and the pressure stayed the same?

Temperature would rise, causing the gas to move faster less volume of gas would be used.

The amount of force exerted on a given area of surface is called pressure. You can think of pressure as the number of times the particles of a gas hit the inside of their container. What is pressure?

The amount of force exerted on a given area of surface

You use physical properties every day. For example, physical properties help you determine if your socks are clean (odor), if your books will fit into your backpack (volume), or if your shirt matches your pants (color). List more examples of physical properties.

Thermal Conductivity - the rate at which a substance transfers heat. State - The physical form in which a substance exist Ice cube to water Solubility - The ability of a substance to dissolve in another substance. (Flavored Drink mix dissolves in water) Ductility - ability of a substance to be pulled into a wire.

What physical property do the following substances have in common: water, oil, mercury, and alcohol?

They all have density

Do objects with large masses always have large weights? Explain.

Yes it contains more matter inside of the object.

A graduated cylinder is used to measure: a. volume. b. weight. c. mass. d. inertia.

a Volume

A physical change is a change that affects one or more physical properties of a substance. Imagine that a piece of silver is pounded and molded into a heart-shaped pendant. This change is a physical one because only the shape of the silver has changed. The piece of silver is still silver. Its properties are the same. What is physical change?

a change of matter from one form to another without a change in chemical properties

What is physical change?

a change of matter from one form to another without a change in chemical properties

Questions help someone gather information about color, odor, mass, and volume. Each piece of information is a physical property of matter. A physical property of matter can be observed or measured without changing the matter's identity. For example, you don't have to change an apple's identity to see its color or to measure its volume. What is physical property of matter?

a characteristic of a substance that does not involve a chemical change, such as density, color, or hardness

Weight is a measure of gravitational force and is expressed in the SI unit of force, the newton (N). One newton is about equal to the weight of an object that has a mass of 100 g on Earth. So, if you know the mass of an object, you can calculate the object's weight on Earth. Weight is a good estimate of the mass of an object because, on Earth, gravity doesn't change. One newton is equal to the weight of an object that has _____ on Earth?

a mass of 100 g

What is volume?

a measure of the size of a body or region in three-dimensional space

How are the particles in a crystalline solid arranged?

a very orderly, three-dimensional arrangement

The units of density for a rectangular piece of wood are a. grams per milliliter. b. cubic centimeters. c. kilograms per liter. d. grams per cubic centimeter.

a. grams per milliliter.

How are the particles in a amorphous solid arranged?

amorphous solid are not arranged in any particular pattern.

The volume of a solid is measured in a. liters. b. grams. c. cubic centimeters. d. All of the above

c. cubic centimeters

Particles of a solid _________

do not move fast enough to over-come the strong attraction between them. So they are close together and vibrate in place.

Crystalline solids _________

have a very orderly, three-dimensional arrangement of particles. The particles of crystalline solids are in a repeating pattern of rows. Iron, diamond, and ice are examples of crystalline solids.

Imagine kicking a soccer ball that has the mass of a bowling ball. It would be not only painful but also very difficult to get the ball moving in the first place! The reason is inertia (in UHR shuh). Inertia is the tendency of an object to resist a change in motion. What is Inertia?

the tendency of an object to resist a change in motion unless an outside force acts on the object

What is formula used to find the volume of a cube or rectangular object?

volume = length × width × height.

A nugget of gold is placed in a graduated cylinder that contains 80 mL of water. The water level rises to 225 mL after the nugget is added to the cylinder. What is the volume of the gold nugget?

225 ml - 80 ml = 145 ml The volume of the gold nugget is 145 ml

One newton equals about 100 g on Earth. How many newtons would a football weigh if it had a mass of 400 g?

400 divided by 100 = 4 newtons

The density of an object is 5 g/cm3, and the volume of the object is 10 cm3. What is the mass of the object?

5 g/cm3 = 10 cm3 / m m=5

Whatis Charle's Law?

States that the volume of a fixed mass of gas at constant pressure varies directly with the Kelvin temperature. As the temperature decreases, the volume decreases. As the temperature increases, the volume increases.

What is temperature?

a measure of how hot (or cold) something is; specifically, a measure of the average kinetic energy of the particles in an object

Volume is the amount of space that an object takes up. But because the particles of a gas spread out, the volume of any gas depends on the container that the gas is in. For example, have you seen inflated balloons that were twisted into different shapes? Shaping the balloons was possible because particles of gas can be compressed, or squeezed together, into a smaller volume. But, if you tried to shape a balloon filled with water, the balloon would probably explode. It would explode because particles of liquids can't be compressed as much as particles of gases. __________ is the amount of space an object takes up.

Volume

Surface tension is a force that acts on the particles at the surface of a liquid. Surface tension causes some liquids to form spherical drops, like the beads of water. What happens to water as a result of surface tension?

Water forms spherical drops (beads) as a result of surface tension.

A chemical change happens when one or more substances are changed into new substances that have new and different properties. Chemical changes and chemical properties are not the same. Chemical properties of a substance describe which chemical changes will occur and which chemical changes will not occur. But chemical changes are the process by which substances actually change into new substances. What is chemical change?

a change that occurs when one or more substances change into entirely new substances with different properties

What Happens During a Chemical Change?

A fun way to see what happens during chemical changes is to bake a cake. You combine eggs, flour, sugar, and other ingredients, as shown in Figure 4. When you bake the batter, you end up with something completely different. The heat of the oven and the interaction of the ingredients cause a chemical change. The result is a cake that has properties that differ from the properties of the ingredients.

Density is a physical property that describes the relationship between mass and volume. Density is the amount of matter in a given space, or volume. A golf ball and a table-tennis ball have similar volumes. But a golf ball has more mass than a table-tennis ball does. So, the golf ball has a greater density. Which has greater density a tennis ball or golf ball?

A golf ball is denser than a table-tennis ball because the golf ball contains more matter in a similar volume.

Use each of the following terms in a separate sentence: physical property and physical change.

A red wooden cube is a physical property. If you break the cube in half it is a physical change.

Classify each substance according to its state of matter: apple juice, bread, a textbook, and steam.

Apple Juice - Liquid Bread - Solid A Textbook - Solid Steam - Gas

How does a chemical change differ from a chemical property?

Chemical property is a property of matter that describes a substance's ability to participate in chemical reactions. Chemical Change - a change that occurs when one or more substances change into entirely new substances with different properties

The Statue of Liberty was originally a copper color. After being exposed to the air, she turned a greenish color. What kind of change happened? Explain your answer.

Chemical property, because the oxygen and air caused a reaction to the copper.

A Change in Composition Physical changes do not change the composition of a substance. For example, water is made of two hydrogen atoms and one oxygen atom. Whether water is a solid, liquid, or gas, its composition is the same. But chemical changes do alter the composition of a substance. For example, through a process called electrolysis, water is broken down into hydrogen and oxygen gases. The composition of water has changed, so you know that a chemical change has taken place. Determining physical change and chemical change depends on ____________.

Composition -if the composition is not changed, it is a physical change. If the composition changes, it a chemical change.

The SI unit of mass is the kilogram (kg), but mass is often expressed in grams (g) and milligrams (mg), too. These units can be used to express the mass of any object in the universe. What is the SI Unit of mass expressed as?

Kilograms (kg)

What do you think would change about orange juice if you poured the juice from a can into a glass? Would the volume of juice be different? Would the taste of the juice change?

Liquids Change Shape but Not Volume. The only thing that would change when the juice is poured into the glass is the shape of the juice. The shape changes because juice is a liquid. Liquid is the state of matter that has a definite volume but takes the shape of its container.

Liters (L) and milliliters (mL) are the units used most often to express the volume of liquids. The volume of any amount of liquid, from one raindrop to a can of soda to an entire ocean, can be expressed in these units. What are two units used to express volume?

Liters (L) and milliliters (mL) are the units used

From a scientific point of view, you have at least one characteristic in common with these things. You, the toaster, the bowl, the soup, the steam, the glass tubing of a neon sign, and the glowing gas are made of matter. But exactly what is matter? Matter is anything that has mass and takes up space. It's that simple! Everything in the universe that you can see is made up of some type of matter. What is matter?

Matter is anything that has mass and takes up space.

The terms mass and weight are often used as though they mean the same thing, but they don't. Weight is a measure of the gravitational (GRAV i TAY shuh nuhl) force exerted on an object. Gravitational force keeps objects on Earth from floating into space. The gravitational force between an object and the Earth depends partly on the object's mass. The more mass an object has, the greater the gravitational force on the object and the greater the object's weight. But an object's weight can change depending on its location in the universe. An object would weigh less on the moon than it does on Earth because the moon has less gravitational force than Earth does. Does mass and weight mean the same thing? Why or Why not?

No mass and weight does not mean the same. Weight has to do with the amount of gravitation force. EX: Earth has a strong gravitational force allowing items to not float, where as the moon's gravitational force is less making the object weigh less and float about space.

Can physical and chemical changes be reversed? Many physical changes are easily reversed. They do not change the composition of a substance. For example, if an ice cube melts, you could freeze the liquid water to make another ice cube. But composition does change in a chemical change. So, most chemical changes are not easily reversed. Can the baking of a cake be reversed back to it's original ingredients?

No, because the composition has been changed.

Particles of Matter Matter is made up of tiny particles called atoms and molecules (MAHL i kyoolz). These particles are too small to see without a very powerful microscope. Atoms and molecules are always in motion and are always bumping into one another. The particles interact with each other, and the way they interact with each other helps determine the state of the matter. Describes three states of matter—solid, liquid, and gas—in terms of the speed and attraction of the particles.

Particles of a solid Particles of liquid Particles of gas

The properties that are most useful in identifying a substance are characteristic properties. These properties are always the same no matter what size the sample is. Characteristic properties can be physical properties, such as density and solubility, as well as chemical properties, such as flammability and reactivity. Scientists rely on characteristic properties to identify and classify substances. Compare the two Physical Properties vs Chemical Properties.

Physical property is a characteristic of a substance that does not involve a chemical change, such as density, color, or hardness. Chemical property is a property of matter that describes a substance's ability to participate in chemical reactions.

Another characteristic of all matter is mass. Mass is the amount of matter in an object. For example, you and a peanut are made of matter. But you are made of more matter than a peanut is, so you have more mass. The mass of an object is the same no matter where in the universe the object is located. The only way to change the mass of an object is to change the amount of matter that makes up the object. What is mass?

The amount of matter in an object.

All matter takes up space. The amount of space taken up, or occupied, by an object is known as the object's volume. Your fingernails, the Statue of Liberty, the continent of Africa, and a cloud have volume. And because these things have volume, they cannot share the same space at the same time. Even the tiniest speck of dust takes up space. Another speck of dust cannot fit into that space without somehow bumping the first speck out of the way. What is Volume?

The amount of space taken up, or occupied, by an object

In your science class, you'll probably use a graduated cylinder instead of a measuring cup to measure the volume of liquids. Graduated cylinders are used to measure the liquid volume when accuracy is important. The surface of a liquid in any container, including a measuring cup or a large beaker, is curved. The curve at the surface of a liquid is called a meniscus (muh NIS kuhs). To measure the volume of most liquids, such as water, you must look at the bottom of the meniscus. The meniscus looks flat because the liquid is in a wide container. What is meniscus? How is it measured?

The curve at the surface of a liquid. To measure the volume of most liquids, such as water, you must look at the bottom of the meniscus.

Knowing the density of a substance can also tell you if the substance will float or sink in water. If the density of an object is less than the density of water, the object will float. Likewise, a solid object whose density is greater than the density of water will sink when the object is placed in water. What will happen to an object placed in water if the object's density is less than water's density?

The object will float

Mass is a measure of inertia. An object that has a large mass is harder to get moving and harder to stop than an object that has less mass. Why would one object be harder to stop or get moving than another object?

The reason is that the object with the large mass has greater inertia. Example, imagine that you are going to push a grocery cart that has only one potato in it. Pushing the cart is easy because the mass and inertia are small. But suppose the grocery cart is stacked with potatoes. Now the total mass—and the inertia—of the cart full of potatoes is much greater. It will be harder to get the cart moving. And once the cart is moving, stopping the cart will be harder.

How much helium is needed to fill a parade balloon? The answer depends on the outdoor temperature. Temperature is a measure of how fast the particles in an object are moving. The faster the particles are moving, the more energy they have. So, on a hot day, the particles of gas are moving faster and hitting the inside walls of the balloon harder. Thus, the gas is expanding and pushing on the walls of the balloon with greater force. If the gas expands too much, the balloon will explode. But, what will happen if the weather is cool on the day of the parade? The particles of gas in the balloon will have less energy. And, the particles of gas will not push as hard on the walls of the balloon. So, more gas must be used to fill the balloons. How much gas moves depends on ________

The temperature. When the temperature is warmer, the particles move faster using less gas. When the temperature is colder, the gases move slower using more gas.

Physical properties are not the only properties that describe matter. Chemical properties describe matter based on its ability to change into new matter that has different properties. For example, when wood is burned, ash and smoke are created. These new substances have very different properties than the original piece of wood had. Wood has the chemical property of flammability. Flammability is the ability of a substance to burn. Ash and smoke cannot burn, so they have the chemical property of nonflammability. What is chemical property?

a property of matter that describes a substance's ability to participate in chemical reactions

Rusting is an example of a S8P1.e a. physical property. b. physical change. c. chemical property. d. chemical change.

a. physical property.

Boyle's law describes the relationship between a. volume and pressure. b. temperature and pressure. c. temperature and volume. d. All of the above

a. volume and pressure.

Amorphous solids ________

are made of particles that do not have a special arrangement. So, each particle is in one place, but the particles are not arranged in a pattern. Examples of amorphous solids are glass, rubber, and wax.

One property that all particles of matter have in common is they S8P1.c a. never move in solids. b. only move in gases. c. move constantly. d. None of the above

c. move constantly.

List five physical properties.

color, odor, mass, magnetism, and volume

There are two kinds of solids—crystalline (KRIS tuhl in) and amorphous (uh MAWR fuhs). Crystalline solids have a very orderly, three-dimensional arrangement of particles. The particles of crystalline solids are in a repeating pattern of rows. Iron, diamond, and ice are examples of crystalline solids. What are the two kinds of solids?

crystalline & amorphous

The volume of any solid object is expressed in cubic units. The word cubic means "having three dimensions." In science, cubic meters (m3) and cubic centimeters (cm3) are the units most often used to express the volume of solid things. The 3 in these unit symbols shows that three quantities, or dimensions, were multiplied to get the final result.There are formulas to find the volume of regularly shaped objects. For example, to find the volume of a cube or a rectangular object, multiply the length, width, and height of the object. volume = length × width × height. What units are most used to express the volume of solid things?

cubic meters (m3) and cubic centimeters (cm3)

To find an object's density (D), first measure its mass (m) and volume (V). Then, use the equation below. Density (d) = mass (m) / Volume (v) What is the density of an object that has a mass of 350 g and a volume of 95 cm3? Would this object float in water? Explain.

d = 350 / 95 cm3 d= 3.68 (cm3) If the density of water is more than 3.68 cm3, the item would more than likely float because it is less dense than water.

Which of the following is matter? a. dust b. the moon c. strand of hair d. All of the above

d. All of the above

Mass is measured in a. liters. b. centimeters. c. newtons. d. kilograms.

d. kilograms

Other physical properties, such as magnetism, the ability to conduct electric current, strength, and flexibility, can help someone identify how to use a substance. For example, think of a scooter with an electric motor. The magnetism produced by the motor is used to convert energy stored in a battery into energy that will turn the wheels. What physical property is used when measuring the ability to conduct electricity?

magnetism

Particles of liquid _______

move fast enough to overcome some of the attraction between them. The particles are close together but can slide past one another.

What are the three most familiar states of matter?

solid, liquid, and gas.

What is pressure?

the amount of force exerted per unit area of a surface

Even in a bottle, a marble keeps its original shape and volume. The marble's shape and volume stay the same no matter what size bottle you drop it into because the marble is a solid. A solid is the state of matter that has a definite shape and volume. What is a solid state of matter?

the state of matter that has a definite shape and volume.


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