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Name _______________________ Mr. Taylor-Waldman

8th Grade Science Final REVIEW – Final is Thursday, June 2

Use this review sheet as an OUTLINE to help you prepare for the science final. Do not study ONLY from this review sheet, but instead, use this ALONG WITH your class

notes, textbooks, labs, quizzes, tests, handouts and homework sheets from the second semester.

Format for the final: 65 – 75 multiple-choice questions 4 – 7 long answer questions

A. Atoms, Periodic Table and Electricity Unit

Atoms and the Periodic Table

Chapter 3, Section 1: Introduction to Atoms (CBB pages 74-79)

Terms atom: smallest unit of any element or type of matter proton: positively charged particle located ___________________. neutron: neutrally charged particle located in the nucleus electron: ___________________ charged particle orbiting in a field around the nucleus atomic number: the number of protons in an atom mass number: the sum of ___________________ and neutrons in an atom’s nucleus isotope: atoms with the same number of protons but a different number of _______________

Important Concepts 1. Protons and neutrons account for most of an atom’s ___________________, while electrons account for most of an atom’s ___________________. 2. The mass of 1 proton = 1 neutron = approximately _________________electrons. 3. In a normal stable atom, the number of protons is the same as the number of electrons. 4. ________________ is the flow of energy through electrons.

Chapter 3, Section 2: Organizing the Elements (pages 80-87)

Terms atomic mass: the _________________ __________ of all of the isotopes in an element’s atoms period: a horizontal row of elements in the periodic table group: a vertical column of elements in the periodic table

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Important Concepts 1. The properties of the elements change in a predictable way as you move from left to right across the periodic table. 2. The elements in each _____________have properties than are the same. 3. The modern periodic table is organized in order of increasing __________ ____________, while Mendeleev’s original periodic table was organized by increasing atomic mass.

Chapter 3, Section 3: Metals (pages 88-95)

Terms malleability: material that can be bent, hammered, or rolled into flat sheets ductility: material that can be pulled out or drawn into long _________________ conductivity: the ability of a substance to transfer _____________or electricity reactivity: the ease and speed with which an element reacts with other elements or compounds

Important Concepts 1. Elements are classified as metals based on their physical and chemical properties. 2. The reactivity of metals ___________________ as you move across the periodic table from left to right. 3. Elements with an atomic number higher than radium (#92) are created synthetically, through the use of ___________________. 4. Know the basic properties and locations in the periodic table of the following metal groups: alkali metals (group 1), alkali earth metals (group 2), transition metals, lanthanides, actinides.

Chapter 3, Section 4: Nonmetals and Metalloids (pages 98-105)

Terms nonmetal: an element that lacks the properties of metals and is a bad conductor of electricity and ______________ metalloid: an element with properties of both metals and nonmetals semiconductor: an element with a varying ability to conduct electricity (acts like a “switch”)

Important Concepts 1. The most useful property of metalloids is their varying ability to conduct electricity. 2. Group 17 (halogens) are highly reactive nonmetals, and group 18 (noble gases) are unreactive.

The Element Project

Important Concepts 1. Be able to describe, in detail, different aspects of your element from our Element Project. The more you can say about your element, the more you’ll earn any questions on the final about it. Make sure you know:

where and when your element was discovered and who discovered it what your element is used for, and its physical and chemical properties

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If your element is a metal, nonmetal, metalloid, or synthetic element

Electricity

Terms battery: a power source that uses a chemical reaction to separate electrons and build up a positive and negative charge in order to produce an electrical current LED: light-emitting diode - type of light bulb where electricity flows in only ____ _____________ post: positive and longer side of an LED anvil: negative and shorter side of an LED conductor: a material that easily transfers electricity insulator: a material that resists and stops the flow of electricity Important Concepts 1. In a(n) ___________ circuit, electricity can flow without interruption, but in a(n)___________ circuit there is a break in the flow of electricity. 2. Current is measured in Amps. 1 Amp is 6.241 x 1018 electrons (1 coulomb) per second going through the wire. 3. A measure of a battery’s total storage or “life” is measured in Amp Hours (Ah). 4. A battery with 20 Amp Hours will produce 20 Amps for 1 hour, or 10 Amps for ___ hours.

Ohm’s Law: Voltage, Current, and Resistance

Terms voltage (V): amount of pressure or force causing a flow of electrons, measured in volts current (I): measure of the _________ of electrical flow. measured in amps resistance (R): opposition to current flow, measured in ohms Ω Ohm’s law: a law relating the voltage, current, and resistance in an electrical circuit

Important Concepts 1. Make sure you understand the “water analogy” in the picture above, which describes the relationship between voltage, resistance and current. 2. Voltage, current, and resistance can all be calculated using the simple equations illustrated in the triangle above.

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Stem Lab #6: Building Circuits

Terms series circuit: a circuit through which electricity can only flow in one path parallel circuit: a circuit through which electricity is able to flow in multiple paths voltmeter: a device used to measure the voltage of a circuit or power source ammeter: a device used to measure the _____________ in a circuit

Important Concepts 1. In a ___________ circuit, if one part of the circuit is disconnected, the entire circuit loses electricity. 2. Series circuits divide the battery’s voltage across all loads (lamps) 3. Voltage does not decrease in a parallel circuit when more loads are added. 4. Know how to describe, in detail, how to use a voltmeter and ammeter.

Atoms, Periodic Table and Electricity Review Questions 1. What are the charges and locations of the three subatomic particles?

2. What is an isotope?

3. What is an atom’s mass number?

4. What is an atom’s atomic mass, and why does it usually end in a decimal?

5. How many protons and neutrons are in the following isotopes (use your textbook or an online periodic table to find the atomic number of each element)?

a) Titanium–45 b) Chlorine–32 c) Zinc–58 d)Silicon–32

P ____ N ____ P ____ N ____ P ____ N ____ P ____ N ____

6. Identify and explain the physical property of metals that relates to electricity.

7. How did Mendeleev organize his periodic table, and how is the modern table organized?

8. How do the properties of metals change from left to right across the periodic table, and why does this happen?

9. Describe as much as you can about the element that you wrote about and researched for the element project.

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10. Explain three different aspects of electricity that you learned from either STEM Lab #6 (Circuit Building) or STEM Lab #7 (Squishy Circuits)

11. What is one property of metalloids and what type of device can metalloids such as silicon be used to produce?

12. What is the difference between an insulator and a conductor? What kind of elements are good conductors of electricity, and which are good insulators?

13. What is the difference between a parallel and a series circuit? What would happen if you disconnected one bulb from a 4-bulb series circuit? What would happen if you disconnect one bulb from a 4-bulb parallel circuit?

14. An alarm clock draws 0.8 A of current when connected to a 120 volt circuit. Calculate its resistance.

15. An electric heater works by passing a current of 120 A through a coiled metal wire, making it red hot. If the resistance of the wire is 1.2 ohms, what voltage must be applied to it?

16. A 15 volt car battery pushes charge through the headlight circuit with a resistance of 10 ohms. How much current is passing through the circuit?

17. You have a large portable audio system that takes 8 D-cell batteries. If the current in the audio system is 5 amps, what its resistance? (Hint: A D-cell battery has 1.5 volts.)

18. Thinking back to the last two STEM labs on building series and parallel circuits, discuss the differences that you observed in bulb brightness, voltage, and current. What changed in the series circuit when you switched from two bulbs to four bulbs. Make the same comparison for the parallel circuit when you increased the number of bulbs. Explain your observations based on your understanding of voltage, current, resistance, and Ohm’s Law.

Use the four circuit boards below to answer the remaining questions.

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19. Which board shows a 3-bulb

parallel circuit? ______

20. Which board shows a 3-bulb series circuit? ______ 21. Describe the problem with the setup in board D, how to fix it, and identify the kind of circuit it would be once fixed.

22. Which board(s) would have the brightest bulbs? Which would have the dimmest?

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B. Engineering Materials and Recycling Unit

Types of Materials Terms polymer: a large, complex molecule built from smaller molecules joined together in a _______________ _______________ monomers: smaller molecules from which a polymer is built plastic: a commonly used material that is considered to be a __________________ polymer composite: a material, like _______________, that is made from a combination of two or more substances, to create a new material with different properties.

Important Concepts 1. Polymers exist in both __________________and synthetic form. 2. While polymers are inexpensive and easy to manufacture, a problem with polymers is that many of them don’t get recycled, and instead end up as pollution.

Great Pacific Garbage Patch Terms gyre: a large, circular system of ocean currents and _______________ The Great Pacific Garbage Patch: a large area in the North Pacific Area that contains high concentrations of trash, mostly plastic bioaccumulation: the process through which chemicals such as DDT and PCB’s become increasingly concentrated higher up the food chain microplastics: tiny fragments of plastic 5mm and smaller biodegradable: material that is decomposed by bacteria into __________________ photodegradable: material that is broken down by __________________

Important Concepts 1. The Pacific Gyre covers an area of 7.7 million square miles in the North Pacific Ocean. 2. Plastic is the most common material in the GPGP because it is inexpensive, found everywhere, and _________________. 3. 80% of the trash in the GPGP comes from land sources and 20% comes from ocean activities.

Paper Recycling Project At School 1. On the final, be ready to answer questions and discuss the school-wide paper recycling program, and the individual project that you worked on.

2. Make sure that you can relate both the school-wide program and your individual project to the steps of the engineering design process.

3. Be prepared to discuss what facts and lessons you learned from the paper recycling project.

4. Be able to discuss and answer basic questions about what you learned from the trip to the SIMS recycling facility.

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Engineering Materials and Recycling Unit Review Questions 1. What is a polymer and what kind of polymer is plastic?

2. Where in the world is the GPGP (be specific) and why is plastic the most common kind of trash found there?

3. Describe two ways in which plastic from land ends up in the GPGP.

4. What is bioaccumulation and what two chemical are known to bioaccumulate in the GPGP?

5. Who is credited with discovering the GPGP, and how and when did he discover it?

6. Why is this man critical of recycling, and what does he think is the most effective solution to improve the situation in the GPGP?

7. Is it possible to clean up all of the plastic in the GPGP? Why or why not?

8. According to our survey of 8th graders, what was identified as the most commonly thrown-away yet recyclable material? What material was the second most common?

9. How did our school-wide paper recycling project relate to the engineering design process?

10. Describe the individual project you worked on, and how it was designed to help enhance recycling at MDY?

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11. Briefly describe how the process of paper recycling works. What material does a lot of recycled paper in New York get turned into?

12. In your opinion, what were some of the biggest challenges in creating a successful paper recycling program at school? What improvements can you think of that would help this or any other school-wide recycling program function more effectively? (Be specific!)

13. What are four different things (either factual concepts or overall lessons) that you learned about recycling as part of this unit?

C. Weather and Climate

Chapter 1, Section 1: The Air Around You (p. 6-9) Terms atmosphere a layer of ______________ that surrounds a planet and weather the condition of earth’s atmosphere at a particular time and place meteoroid a solid object floating through outer space ozone a compound composed of three ______________ atoms (O3) water vapor water in the form of a ______________

Important Concepts 1. Air is matter and has _______, volume and density like all matter. The atmosphere is composed of a mixture of atoms and molecules of many different gases, and also particles of dust, smoke, and other chemicals. 2. The Earth’s atmosphere is made of ______________ (78%), oxygen (21%), argon (0.93%), carbon dioxide (0.038%), water vapor (up to 1%), and other gases and particulates. 3. Oxygen in the atmosphere is important in two major ways: ____________ for living organisms, and it allows for the ______________ of fuels such as gasoline and coal. 4. Water vapor plays an important role in regulating earth’s weather. 5. The Earth’s atmosphere protects life in four major ways: it provides oxygen, it keeps the earth warm by trapping sun’s heat, it blocks harmful ______________ radiation, and it prevents meteoroids from hitting Earth’s surface.

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Chapter 1, Section 2: Air Pressure (p. 10-14) Terms pressure the amount of force pushing down on a given area air pressure the result of the weight of a column of air pushing down on a specific area -- this

column extends from the ground to the ________________ barometer an instrument used to measure pressure mercury barometer a tube partially filled with mercury and submerged in a dish of Hg

High pressure = mercury rising Low pressure = ______________ in mercury level

aneroid barometer an airtight metal chamber that flexes in and out as air pressure changes altitude distance above ______________

Important Concepts 1. The weight of the atmosphere is constantly pushing on the surface of the Earth due to ____________. We call this weight ___________________. 2. Denser air exerts more pressure than less dense air. Frequent changes in air density can make air pressure change from day to day and from place to place. 3. Air pressure and density ______________ as altitude increases. 4. The low density of air at high altitudes makes it hard to breathe because there is ________________________. 5. Higher air pressure systems usually bring about ____________________ weather, whereas low air pressure systems usually cause __________________________ weather. 6. Air pressure is measured in inches of mercury and millibars. 1 inch mercury = _____ millibars.

Chapter 1, Section III: Layers of the Atmosphere (p. 16-21) Terms

Layer Altitude As altitude ↑, temp Characteristics

Troposphere 0–12 km Decreases Where weather occurs, contains almost all of the mass of the air in the atmosphere

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12–50 km Increases (due to the warm ozone layer)

Contains the ozone layer, which blocks harmful UV light

Mesosphere 50–80 km _________________ Prevents meteoroids from hitting Earth

Thermosphere Ionosphere: 80–400km

Increases (because light strikes the thermosphere first, making particles move fast)

Where the auroras occur

Exosphere: Above 400 km

Where satellites orbit

Concepts 1. Scientists divide the Earth’s atmosphere into four main layers classified according to their changes in ______________ as compared to altitude. 2. Even though temperatures in the thermosphere can reach 1800° C, the density of air in the thermosphere is so low that you would actually ________________.

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Chapter 1, Section IV: Air Quality/Pollution (p. 22-25) Terms pollutants substances in the water, air, and soil that are harmful to life fossil fuels underground fuels such as coal, oil, and gasoline which are thought to come

from dead plants and animals smog a mixture of ______________ and fog photochemical smog a brown haze formed when sunlight reacts with gases from burning fossil fuels London Killer Fog an event in London in 1952 where a thick smog of sulfur dioxide (from coal

smoke) killed thousands of people acid rain rain that is more acidic than normal

Concepts 1. Air pollution can come from ____________ sources (forest fires, dust storms, volcanoes and pollen) or from ______________ sources (arming, construction, and the burning of fossil fuels). 2. ___________________________ is the greatest contributor to air pollution, and produces pollutants such as carbon monoxide (CO), carbon dioxide (CO2), nitrogen dioxide (N02), and sulfur dioxide (SO2).

Chapter 2, Section 1: Weather Factors (p. 34-69) Terms _________________ energy energy that travels through space as waves – light and radiation from

the sun are examples of this radiation direct transfer of energy by electromagnetic waves infrared radiation energy that we feel as ____________ and has wavelengths that are

____________ than visible light ultraviolet radiation energy from the sun with wavelengths ____________ than visible light

and longer than x-rays

Concepts 1. The sun releases energy in three different forms of electromagnetic waves. 2. This energy reaches earth as visible light, infrared radiation, and ultraviolet radiation. 3. 50% of incoming energy from the sun is absorbed by Earth’s surface, ______ is absorbed by the atmosphere, 25% is reflected by the atmosphere back into space, _____ is reflected off the surface back toward the atmosphere 4. Colors that we see are ________________ that particular wavelength of light and absorbing all other colors. A blue shirt appears therefore ________________ red, green, and yellow wavelengths of light.

Chapter 2, Section 2: Heat Transfer (p. 42 – 45) Terms temperature the ___________________ of the random motion of particles thermometer an instrument used to measure temperature heat the transfer of thermal energy from ____ matter to _____ convection the transfer of heat by the movement of a fluid (gas or liquid) global warming the gradual rise of Earth’s average annual temperature

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Important Concepts 1. Heat is transferred in three ways: radiation, conduction and convection. 2. Radiation, conduction and convection work together to transfer heat throughout the troposphere. The sun transfers heat to Earth’s surface through radiation. Some of this heat is transferred to the thin layer of air directly touching the ground through _______________. This heat air then rises, while cooler air sinks and takes its place. This occurs through convection currents. 3. Earth’s average yearly temperatures have been rising due to increasing emissions of CO2 worldwide. This is causing glaciers to melt, which creates a rise in sea levels. 4. Most heat transfer in the troposphere occurs through __________________.

Chapter 2, Section 3: Winds (p. 46-53) Terms wind the movement of air from ______ pressure to ______ pressure anemometer an instrument used to measure wind speed local winds winds that blow over short distances, are inconsistent, and are caused

by the unequal heating of Earth’s surface within a small area global winds winds that blow steadily in specific directions over long distances sea breeze local winds that blow from an __________ toward ___________ land breeze local winds that blow from land toward the ocean

Concepts 1. Wind is the movement of air from an area of high pressure to low pressure. Differences in air pressure are caused by ______________ of Earth’s surface. Cool, dense air with higher air pressure flows underneath warm, less dense air with lower pressure. 2. A sea breeze typically occurs during the day, when air temperatures over _______ rise quicker than those over _______. 3. A land breeze typically occurs during the night, when air temperatures over land cool more rapidly than the air over water.

Chapter 2, Section 4: Water in the Atmosphere (p. 54-60) Terms water cycle movement of water between the atmosphere and Earth’s suface humidity measure of the amount of _______________ in the air relative humidity ______________ of water vapor actually in the air compared to the

total amount the air can hold at a given temperature psychrometer an instrument used to measure relative humidity dew point temperature at which water vapor condense into liquid water cumulus cloud mid-low level clouds that resemble fluffy, round heaps of cotton stratus cloud low level sheet of clouds that form in _____________ cirrus clouds` high level feathery clouds that are made up of ice crystals nimbus, nimbo word indicating a cloud likely to produce rain cirro- a word indicating a high altitude cloud alto- a word indicating a medium altitude clou

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Concepts 1. The water cycle is composed of three steps: evaporation, _______________ and precipitation. Evaporation occurs from bodies of water such as oceans, rivers and lakes, and also from plants. Condensation occurs when water vapor cools and forms water droplets, forming clouds. _______________ occurs when the water from clouds falls to earth’s surface 2. Two conditions are necessary for clouds to form. The first condition is ___________________. Water will remain as vapor until temperatures are low enough to allow for condensation, the point at which clouds are formed. The second necessary condition is the presence of ________________ in the air. Tiny particles of dust, smoke and dirt provide a surface on which water can condense.

Review Questions for Weather and Climate

1. What two gases make up 99% of the atmosphere? What two gases make up most of the remaining 1% of the atmosphere?

2. What are four ways in which Earth’s atmosphere protects life on earth?

3. Where is “good” ozone found in the atmosphere, and what role does it play? Chemical formula? In which layer of the atmosphere is ozone “bad” and why is it bad?

4. What are two reasons why oxygen in the atmosphere is important?

5. The layers of the atmosphere are classified according to changes in what? (Be specific!)

6. In which layer of the atmosphere do most meteors burn up? Why in this layer?

7. What is air pressure? How do air pressure and air density change with altitude?

8. What two devices are used to measure air pressure? How are they different?

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9. Steadily decreasing air pressure readings usually indicate what kind of weather?

10. What are two natural sources of air pollution? What are two human-caused sources?

11. What activity is responsible for causing most of the air pollution on Earth?

12. Based on what we learned in Science World, what effect is global warming having on glaciers, what does this cause as a result, and why is this a threat to a large portion of the world’s population?

13. In one of our science labs we learned that melting glaciers and melting icebergs impact sea-level rise differently. Describe how we tested the effect of melting icebergs on sea level, and what we concluded from this.

14. What are two important facts about the troposphere?

15. The shortest wavelengths of electromagnetic radiation the sun emits are called what?

16. List the three forms of electromagnetic radiation from the sun in order of wavelength (shortest to longest).

17. Explain how we detect each of the three forms of electromagnetic radiation.

18. Describe the three types of heat transfer, and explain how they work together to heat Earth’s troposphere.

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19. What was the London “Killer Fog”? What weather factors caused this to happen? What human related activities led to this event?

20. When you see the color green, which forms of visible light are being reflected and absorbed?

21. You’re frying an egg on a pan that is being heated on a gas stovetop. Which forms of heat transfer are occurring?

22. What method of heat transfer would explain how eagles and hawks can soar upwards without flapping their wings.

23. Explain how a sea breeze works. How and why could this potentially turn into a land breeze at night?

24. What two processes are necessary for cloud formation?

25. Explain the difference between local and global winds.

26. How is wind related to air pressure and air temperature?

27. Explain the three processes that make up the water cycle.

28. What are the three main cloud shapes and at what altitudes are they found?

29. What do the terms nimbo, alto, and cirro mean?