Chem Test 1

physical change

-A change in a substance that does not produce a new substance or a chemical reaction. -Usually produces less energy than chemical reactions Ex) Cutting, heating, squeezing, bending, and dissolving.

chemical change

-A change in a substance that produces a new substance or a chemical reaction. -Usually produces more energy than chemical reactions Ex) rusting (oxidation), smelting, and burning.

reverse osmosis

-A type of filtration that uses a filter with extremely small holes so no solids can come through. You need to put pressure on the water. Can remove dissolved substances. -Ex) creates drinkable ocean water; bottled water

intensive/extensive properties

-The two categories used to classify properties of matter -Extensive properties depend on the amount of matter in a sample. An example of an extensive property is color. -Intensive property depends on the type of matter in a sample, not the amount of matter. An example of an intensive property is mass and weight.

decanting

-When you pour a liquid off of a solid. Carefully pouring of a liquid from a solid or from a heterogenous mixture that is not dissolved. - A way to separate heterogeneous mixtures

'scum' layer

-on top of crust -has most molecular substances -has water, atmosphere, all living things, dirt

We have observed or created ______ Of different pure substances and are creating _______each year.

10s of millions, new ones

malleable

easy to shape or bend

Pure substances

elements and compounds

chemical properties

flammability and reactivity( w/ things like acid)

Main types of matter

glass, plastic, wood, sand, paper, concrete, foam, rubber, etc

How far have we drilled into the Earth?

havent reached the mantle

reactant

A chemical substance that is present at the start of a chemical reaction

How is a compound different from an element

A compound is a combination of two or more elements chemically combined, while an element is the simplest form of matter

48. What is the difference between homogeneous mixtures and heterogeneous mixtures?

A homogeneous mixture is uniform in composition while a heterogeneous mixture is not. Also, homogenous mixtures have one phase, while heterogeneous mixtures have multiple phases.

solubility

A measure of how much solute can dissolve in a given solvent at a given temperature to produce a saturated substance

dissolving followed by gravity filtration

A mixture of two solids, where one will dissolves in water and the other would stay. To get the solid back you could boil the water.

heterogeneous mixture

A mixture that is not uniform in composition; components are not evenly distributed throughout the mixture

heterogenous mixture

A mixture with uneven distribution of different substances, solids, liquids, gases.

Coumpound

A sample of matter that cannot be separated physically but can be separated chemically. Ex) Water, carbon dioxide, hydrogen peroxide.

Element

A sample of matter that cannot be separated physically or chemically. Ex) Iron, nickel, hellium.

chemistry

A scientific study of the different types of matter that do and can exist. Focuses on types of matter and chemical reactions.

mineral

A solid inorganic substance of natural occurrence.

How many phases does a solution have? Explain your answer.

A solution has one phase because it has a uniform composition throughout and is homogenous. An example of this is saltwater.

product

A substance produced in a chemical reaction

29. Identify Name the chemical elements represented by the following symbols: a. C b. Ca c.K d.Au e.Fe f. Cu

A. Carbon b. Calcium c.Potassium d. Gold e. Iron f. Copper

Classify each of the following as homogeneous or heterogeneous mixtures.

A. Chocolate chip ice cream -heterogenous B. Green ink- homogenous C. cake batter- heterogenous D. cooking oil- homogenous E. granite rock -heterogenous F.. saltwater-homogenous G. paint- homogenous oil-based paints are heterogeneous, while watercolor paints are homogenous. H. a silver ring -homogenous. Alloy-mixture of two or more metals. Alloys are always homogenous.

classify each of the following as a chemical change or a physical change. A. Plastic drink bottles are burned in an insert incinerator to generate electricity. B. Digesting a cereal bar. C. Water in a rain puddle evaporates. D. Slicing a tomato for a sandwich E. Plastic drink bottles are recycled to make fiberfill for ski jackets -

A. Plastic drink bottles are burned in an insert incinerator to generate electricity.- chemical B. Digesting a cereal bar.- chemical C. Water in a rain puddle evaporates.- physical D. Slicing a tomato for a sandwich.-physical E. Plastic drink bottles are recycled to make fiberfill for ski jackets -physical

54. Describe the relationship between the three items in each of the following groups. Identify each item as an element, compound, or mixture. a. hydrogen, oxygen, and water b. nitrogen, oxygen, and air c. sodium, chlorine, and table salt d. carbon, water, and table sugar

A.a compound b.mixture c.compound d. Compound; if you heat table sugar it breaks down into water and carbon.

Identify each of the following as an element, compound or mixture. A.iron- B.distilled water- C. laundry detergent- D. Sulfur- E.chicken broth F.sodium fluoride -

A.iron- element B.distilled water- a compound C. laundry detergent- a mixture D. Sulfur- element E.chicken broth- a mixture F.sodium fluoride - compound

60. Classify each of the following as physical or chemical change. For any chemical change, list at least one clue to support your answer. A: A copper wire is bent B: Charcoal burns in a grill C: Bread dough rises when yeast is added D:Sugar dissolves in water.

A: Physical Change B: Chemical change- The change of color displays it is a chemical change. The new substance forming is invisible (carbon dioxide). C: Chemical change- The production of gas displays it is a chemical change. D: Physical change

Fingernail polish remover is a liquid at room temperature. Would you describe acetone in the gaseous state as a vapor or a gas? Explain your answer.

It would be described as a vapor because it is generally a liquid or solid at room temperature.

How are a substance and a solution similar? How are they different?

Both are similar because they have compositions uniformed throughout and one phase. They are different because substances have definite Composition while a solution is a mixture of two or more substances. A solution can be separated physically but a substance can not.

Substances --------) Elements

Chemical

What type of property cannot be observed without changing the composition of a substance?

Chemical changes because the process creates chemical changes. For example, lighting something on fire, which is a chemical change, forms a new substance.

What pure substance can be broken down?

Compounds

52. How could you distinguish an element from a compound?

Compounds can be broken down into simpler substances by chemical means, but elements cannot. Compounds are made of two or more elements, however, elements are the simplest forms of matter and can not be broken down chemically.

How are the items in each of the following pairs similar? How are they different? Copper and silver distilled water and saltwater Table sugar and table salt

Copper and silver- They are both elements, and they are both metals. They have different physical properties like color and boiling points. B. distilled water and saltwater-They are both liquids are room temperature, however, saltwater is a mixture while distilled water is a compound. Table sugar and table salt- They are both compounds. They are made up of different elements.

core/mantle/crust

Core- Made up of metals (Nickel and iron alloy) Mantle- Made up of solid rock Crust-Made of minerals

What type of properties can be used to separate mixtures?

Differences in physical properties can be used to separate mixtures. Examples of these physical properties are filtration, the process that separates a solid from the liquid in a heterogeneous mixture. Another physical property used to separate mixtures is distillation when a liquid is boiled to produce a vapor that is then condensed into a liquid.

indefinite volume

Does not have a fixed volume. Gas and plasma have indefinite volumes. Fills the container it is in.

What pure substance can not be broken down?

Elements

63. Which colorless substance is liquid at -30 degrees C?

Ethanol is liquid at -30 degrees C.

47. Explain why sharpening a pencil is a different type of physical change in freezing water to make ice cubes.

Even though sharping a pencil and freezing water is physical changes, they are different because one changes it state of matter. When you sharpen a pencil, a pencil still is in solid form, however, when you freeze water to make ice cubes, it changes from a liquid to a solid-state. You can not reverse sharpening a pencil, but you can reverse freezing water.

Describe the difference between an extensive property and an intensive property and hive an example of each.

Extensive properties depend on the amount of matter in a sample, and an intensive property depends on the type of matter in a sample, not the amount of matter. An example of an extensive property is mass and volume. An example of an Intensive property is an absorbancy.

In general, when would you use filtration to separate a mixture? When would you use distillation to separate a mixture?

Filtration is used to separate a solid from a liquid in a heterogeneous mixture. An example of this is a coffee filter, separating the black solution from the beans. Distillation is used to separate different liquids or homogenous mixtures. For instance, separating water from the other components in tap water.

Classify each of the following as a homogeneous or heterogeneous mixture. Food coloring ice cubes in liquid water Mouthwash mashed, unpeeled potatoes

Food coloring - homogeneous mixture ice cubes in liquid water- heterogeneous mixture Mouthwash- homogeneous mixture mashed, unpeeled potatoes - a heterogeneous mixture

How can you distinguish a substance from a mixture

If the composition of a material is fixed, the material is a substance. If a composition of a material may vary, the material is a mixture.

68. Is malleability an extensive property or an intensive property?

It is intensive because it matters with the type of matter in a sample.

A clear liquid in an open container is allowed to evaporate. After three days, a solid is left in the container. Was the clear liquid an element, a compound, or a mixture, How do you know

It was a mixture because the substances were not chemically combined.

Liquid A and Liquid B are clear liquids. They are placed in open containers and allowed to evaporate. When evaporation is complete, there is a white solid in container B but no solid in container A. From these results, what can you infer about the two liquids

Liquid B was actually a homogenous mixture that contained a dissolved solid. Liquid A had no dissolved substance.

In what way are liquids and gases alike? In what way are liquids and solids different?

Liquids and gases are alike because they both have indefinite volumes and fill the volume take the shape of the container they are put in. Also, Liquids and solids are different because liquids have an indefinite shape, but solids have a definite shape.

Give three examples of when you have separated mixtures at home.

Making coffee using coffee beans, making tea using leaves, and boiling water. Straining pasta, taking something out of a salad,

Used table 2.1 to identify four substances that undergo a physical change if the temperature is reduced from 50 degrees Celsius to -50 degrees C. What is the physical change that takes place in each case?

Mercury would freeze. Bromine would freeze. Chlorine would condense. Finally, water will freeze.

How are mixtures classified?

Mixtures are classified based on the distribution of their components, mixtures can be classified as heterogeneous mixtures or as homogeneous mixtures. An example of a homogeneous mixture is olive oil and vinegar. An example of a heterogeneous mixture is chicken noodle soup.

homogenous mixture (also known as solution)

More than one type of matter that is mixed perfectly

Why in their appearance displays that they are elements?

Nothing

Explain the term phase as it relates to homogeneous and heterogeneous mixtures.

Phase is used to describe any part of a sample with uniform composition and properties. A homogeneous mixture consists of a single-phase, while a heterogeneous mixture consists of two or more phases. Sugar and water is one phase, however, flour and water are two phases.

Mixtures --------) Substances

Physical

Describe the two categories used to classify physical changes.

Physical changes are classified as reversible or irreversible. An example of reversible changes is melting an ice cube and re-freezing it again. An example of an irreversible change is cutting your nails or hair.

Explain why samples of platinum and copper can have the same extensive properties but not the same intensive properties.

Platinum and copper can have the same extensive properties because they can both be in pieces with the same amount of matter. Moreover, they do not have the same intensive properties because they are not the same type of matter.

Rock= Paper= Scissors=

Rock= Minerals Paper= Molecules Scissors= Metal

distillation

Separation by boiling and collecting substances as they vaporize. Passes vapor through a cooling tube and condenses it back to a liquid.

condensing

The change of state from a gas to a liquid

Name four possible clues that a chemical change has taken place.

The clues to a chemical change include transferring energy, a change in color, the production of gas, or the formation of a precipitate. A change in color, the production of gas, or the formation of a precipitate is evidence of a new substance forming. For example, using natural gas to cook food by heating it.

Is the freezing of mercury a reversible or irreversible physical change? Explain your answer.

The freezing of mercury is a reversible change because it involves a change from one form to another.

distillate

The liquid collected during distillation when the evaporated substance condenses

What is the main difference between physical and chemical changes?

The main difference between physical and chemical changes is that chemical changes produce new substances, however, physical changes do not. For example, ripping paper, which is a physical change, does not create a new substance. But, lighting something on fire, which is a chemical change, forms a new substance. Energy changes in chemical reactions are mostly larger than energy changes in physical changes.

Explain why Mass cannot be used as a property to identify a sample of matter.

The mass of a substance can vary in all types of matter. This means that it can not be used to identify specific substances since it is present in every substance. It is an extensive property. Any two things can have the same mass depending on the size of the sample.

Name two physical properties that could be used to distinguish between water and ethanol.

The melting and boiling are two physical properties that could distinguish water and ethanol.

smelting

The process by which rock (ore) is melted to separate the useful metal from other elements. When rock reacts to form metal

79. Explain why the production of a gas does not always mean that a chemical reaction has occurred.

The production of a gas does not always mean that a chemical reaction has occurred because you have to check if a new substance has formed, and the production of gas can occur without a new substance forming. For example, something could be boiling or soda bubbles (they are not a new substance).

List three physical properties of copper.

Three physical properties of copper are its solid-state, 1084 degrees Celcius melting point, and reddish-yellow. It is a metal that conducts electricity and is malleable. Also, it is shiny and conducts heat.

How does a chemical change affect the composition of matter?

Throughout chemical changes, the composition of matter always changes. A new substance is forming, and an old substance is disappearing. For example, when charcoal is heated and burned, a chemical change occurs.

What is the goal of a distillation? Describe briefly how this goal is accomplished.

To separate a solid and a liquid in a heterogeneous mixture. This is accomplished when a solution is boiled and then condensed from a gas to a liquid. The substances are heated slowly. Then, the mixtures are boiled one at a time and condensed one at a time.

Air is mainly a mixture of nitrogen and oxygen, with small amounts of other Gases such as argon and carbon dioxide. What property could you use to separate the gases in air?

You can separate gases in the air uses fractional distillation. You can turn them into liquids and then distill them until they are separated. You could cool them slowly. The condensing point of nitrogen is -195.8 degrees C, oxygen is -183 degrees C, argon -185 degrees C, CO2 -78. 46 degrees C. The air is 80% nitrogen, 20% oxygen, 1% argon, and less than 0.1 % CO2.If you cool these slowly these gases would condense (liquify or become solid).

Name two methods that can be used to break down compounds into simpler substances.

You can use electrolysis to break down compounds by passing an electric current through the compound, or you can burn a compound to get simpler substances.

What physical properties could be used to separate iron filings from table salt?

You could use a magnet to separate iron filings from table salt because iron is attracted to magnets, while table salt is not. The boiling and melting point. Since these substances have such different boiling points you can boil out the substance with the lower boiling point. Since these substances have different melting points you can melt out the substance with the lower melting point. After melting/ boiling you would need to filter these substances. Solubility is the ability to dissolve in something. The salt will dissolve, but the iron filings would not.

71. You are standing in a kitchen and then in the middle of your surrounding elements, compounds, or mixtures? When you view your surroundings in each location, do you see mostly elements, compounds, or mixtures

You mostly see mixtures. Most people do not have pure elements around them, but they have things made of elements like mixtures. Also, most people do not have compounds around them, however, they have mixtures created by compounds.

Explain Describe a procedure that could be used to separate a mixture of sand and table salt.

You would add water to the mixture and stir. The table salt will dissolve in the water while the sand will not. Then, you put the mixture through filtration which will separate the sand from the saltwater. Then, you boil the saltwater mixture to separate the salt and water because tehy water will evaporate.

homogeneous mixture (solution)

a mixture that is uniform in composition; components are evenly distributed and not easily distinguished

substance (also referred to as 'pure substance')

a sample of matter with both definite and constant composition and distinct chemical properties.

precipitate

a solid that forms and settles out of a liquid mixture

Classify the following properties of the element silicon as chemical or physical properties: A. Plastic drink bottles are burned in an insert incinerator to generate electricity. B. Digesting a cereal bar. C. Water in a rain puddle evaporates. D. Slicing a tomato for a sandwich. E. Plastic drink bottles are recycled to make fiberfill for ski jackets

a. Blue-gray color- physical B. Brittle- physical C. Doesn't dissolve in water-physical D. Melts at 1410 degrees Celsius- physical e. Reacts vigorously was Fluorine-chemical Fluorine is extremely reactive and dangerous.

* 53. Classify the following materials as an element, compound, or mixture. Give reasons for your answers. a. table salt (NaCl) b. salt water c. sodium (Na)

a. Compound; it's a pure substance, it is made up of two elements, it has a chemical formula. b.Mixture; it is a mixture of two substances that are not chemically combined and can be separated physically c.Element

28. Identify Write the chemical symbol for each of the following elements: a. lead b. oxygen c. silver d. sodium e. hydrogen f. Aluminum

a. Pb b.O c. Ag d.Na e.H f. Al

Classify Classify each of these samples of matter as an element, a compound, or a mixture. a. table sugar- b. tap water- c. cough syrup - d. nitrogen -

a. table sugar- compound b. tap water- mixture c. cough syrup -mixture d. nitrogen -element

Any new substance almost always has _____ in it.

carbon

physical properties

color, density, melting/ boiling points, smell, mallaebility.

vapor

describes the gaseous state of a substance that is generally a liquid or solid at room temperature

72. Identify each of the following items as a mixture or compound. Classify the mixtures as homogeneous or heterogeneous. a. raw egg b. ice c. gasoline d. Blood

heterogeneous mixture b.compound c.homogenous mixture d. Heterogeneous mixture

condensed state

liquid and solid states of matter; states in which a substance has a substantially higher density than in the gaseous state. Has a fixed shape.

Everything around us is a

mixture

gravity filtration

separation of a solid and liquid in heterogenous mixtures. (Making coffee from beans).

states of matter

solid, liquid, gas, plasma

centrifuging

spinning a mixture very fast , and the more dense substance will go to the outside.

Mixtures of types of matter is

substances

combustion

the process of burning something

condenser (or cooling tube)

used to condense vapors that is, turn them into liquids by cooling them down. Used in distillation

phase

used to describe any part of a sample with uniform composition and properties