MC Module 1 Tutorial - Mastering Chemistry PDF

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Mastering Chemistry...

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Module 1 Tutorial Due: 11:55pm on Friday, December 22, 2017 To understand how points are awarded, read the Grading Policy for this assignment.

Item 1 Matter is anything that takes up space and has mass. Matter is classified in many different ways, including by its state (solid, liquid, or gas) and by its composition (pure substances or mixtures).

Part A The blue spheres below represent atoms. What state of matter is depicted by each graphic? Graphic A

Graphic B

Graphic C

Drag each item to the appropriate bin.

Hint 1. The properties of solids, liquids, and gases The following chart describes some of the properties of solids, liquids, and gases. State Solid

Atomic/molecular motion

Atomic/molecular spacing

oscillation/vibration about fixed point close together

Shape definite

Volume definite

Liquid free to move relative to one another close together

indefinite definite

Gas

indefinite indefinite

free to move relative to one another far apart

ANSWER:

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solid

gas

Correct

Part B Classify each type of matter as an element, a compound, a heterogeneous mixture, or a homogeneous mixture. Drag each item to the appropriate bin.

Hint 1. How to approach the problem

liquid

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First, identify each type of matter as a pure substance or a mixture. A pure substance has a specific chemical composition, and all samples of the substance have the same composition. A mixture, in contrast, is a combination of substances in which each substance retains its own identity. In addition, mixtures do not have constant composition. Then, further classify each pure substance as either an element or a compound, and classify each mixture as either a heterogeneous mixture or a homogeneous mixture. It may help to use the periodic table to determine whether a substance is an element.

Hint 2. Define the terms Complete each sentence with the appropriate term. Match the words in the left-hand column with the appropriate blank in the sentences in the right-hand column. ANSWER:

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1. Heterogeneous mixtures contain two or more atoms or compounds in variable proportions and do not have uniform composition. 2. Compounds contain two or more elements combined in a fixed proportion.

3. Homogeneous mixtures contain two or more atoms or compounds in variable proportions and have a composition that is the same throughout. 4. Elements contain only one type of atom.

Hint 3. Classify each type of matter as a pure substance or a mixture Classify each type of matter as a pure substance or a mixture. Drag each item to the appropriate bin.

Hint 1. Explanation of the different examples of matter The eleven examples of matter in this item are the following: Air: Air is composed of about 78 nitrogen and 21 oxygen, with traces of argon, carbon dioxide, and other gases. The gases are not chemically bonded to each other. Salt water: Salt water is water that contains dissolved salt. Banana juice with pulp: Banana juice with pulp contains liquid juice, which is mostly water, and some of the fruit solids (pulp). Soil: Soil contains air, minerals, water, and organic matter. Sulfur trioxide: Sulfur trioxide has the formula . Hot coffee: Hot coffee is typically prepared by steeping ground coffee in hot water and then removing the spent coffee grounds. Gold: Gold is a soft yellow metal that is a good thermal conductor. Boron: Boron is a hard metalloid. Sugar: Table sugar (sucrose) has the chemical formula . Calcium: Calcium is a moderately hard, silvery alkaline earth metal. Distilled water: Water has the chemical formula .

ANSWER:

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gold

calcium

boron banana juice with pulp

sugar

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soil

sulfur trioxide air

salt water

hot coffee

distilled water

Hint 4. Descriptions of heterogeneous and homogeneous mixtures Both heterogeneous mixtures and homogeneous mixtures contain two or more atoms or compounds in variable proportions. A heterogeneous mixture has a composition that is not uniform. That is, one part of the mixture has a different composition from another part. A chocolate-chip cookie is one example of a heterogeneous mixture. Heterogeneous mixtures may also have components in different phases. A homogeneous mixture has a composition that is the same throughout. Wine is a homogeneous mixture.

ANSWER:

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sugar gold

boron

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sulfur trioxide

calcium

banana juice with pulp

soil

salt water

hot coffee

air

distilled water

Correct A mixture can contain substances in different states. For example, a glass of ice water contains solid ice and liquid water.

Item 2 First, launch the video below. You will be asked to use your knowledge of chemistry to predict the outcome of a demonstration. Then, close the video window and answer the questions at right. You can watch the video again at any point to review.

Always wear protective clothing, appropriate gloves, and eye gear when in the chemistry lab.

Part A You happen to be visiting Northern California and you are driving by Suisun Bay, a notorious graveyard for old ships. You notice that all of these ships appear be rusting away. Which of the following statements is true?

Hint 1. What is the difference between a chemical change and a physical change? A chemical change is the result of a chemical reaction. A physical change just changes the state of the substance.

ANSWER:

The rusting of the metal is neither a chemical change nor a physical change. The rusting of the metal is a chemical change. The rusting of the metal is both a chemical change and a physical change. The rusting of the metal is a physical change.

Correct

Part B Black ice is a thin layer of water on a sidewalk or road that has frozen after the temperature has dropped below freezing. It is called black ice because the ice nearly invisible, especially when driving in a car at night. Which of the following statements is true?

Hint 1. What is the difference between a chemical change and a physical change? A chemical change is the result of a chemical reaction. A physical change just changes the state of the substance.

ANSWER:

Black ice is neither a chemical change nor a physical change. Black ice is an example of a chemical change. Black ice is both a chemical change and a physical change. Black ice is an example of a physical change.

Correct

Item 3 Matter has both physical and chemical properties and can undergo physical or chemical changes. Physical properties are those that a substance displays without changing its composition, whereas chemical properties are evident only during a chemical change (also called a chemical reaction). In contrast, when a substance undergoes a physical change, it may change appearance, but not its composition.

Part A Classify each of the changes as a physical change or a chemical change. Drag each item to the appropriate bin.

Hint 1. Changes in matter

When matter undergoes a physical change, the appearance or texture of the matter may change, but its composition remains the same. For example, water is made up of molecules whether it is in liquid form or solid form (ice). Thus, the freezing of water is a physical change. When matter undergoes a chemical change, the composition of the matter changes. For example, when iron rusts, the iron atoms combine with oxygen atoms to form a new substance, iron oxide.

Hint 2. Classify descriptions as applying to physical changes or chemical changes Classify the following descriptions by whether they apply to physical changes or chemical changes. Drag each item to the appropriate bin. ANSWER:

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change in composition phase change chemical reaction no new substance produced new substance produced

ANSWER:

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slicing a banana

condensation of water vapors

tearing aluminum foil

carving wax

bleaching hair

silver tarnishing

burning paper

frying a chicken

Correct When tarnish forms on silver, the outer layer of silver atoms has reacted with sulfur to become a new substance, silver sulfide.

Part B Classify each of the properties as a physical property or a chemical property. Drag each item to the appropriate bin.

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Hint 1. The properties of matter Physical properties are properties of matter that can be observed without the matter changing composition. For example, the appearance of a substance can be observed without changing the composition of the substance. Chemical properties are properties of matter that can only be observed when the matter changes composition. For example, the reactivity of a substance can only be observed when the substance is reacting (or changing its composition). A good way to identify chemical properties is to look for properties that seem to describe a chemical reaction. Those that don't appear to describe a chemical reaction are likely to be physical properties. It may help if you think about what you know about the matter before and after the observation. If the matter is the same, then it is a physical property. If the matter is not the same, then it is a chemical property.

Hint 2. Classify general properties as physical properties or chemical properties Classify these properties by whether you would have to perform a chemical reaction to test that property. Drag each item to the appropriate bin. ANSWER:

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flammability

reactivity

corrosiveness

color

odor

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boiling point

appearance

ANSWER:

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the luster of gold jewelry the color of aluminum wire

Correct Score Summary:

the melting point of water the smell of alcohol

the explosiveness of fireworks

Help

the reactivity of copper with oxygen

the flammability of ethanol

Your score on this assignment is 100%. You received 14 out of a possible total of 14 points....