8th Grade Science EOG Review

Multiple Choice

A student is asked to categorize the following items as elements, compounds, or mixtures: copper wire, salt, aluminum foil, baking soda, a piece of granite, and sugar water. He lists ELEMENTS as copper wire, aluminum foil, and baking soda; COMPOUNDS as salt; MIXTURES as the piece of granite. Which is in the wrong category?

• copper wire

• baking soda

• sugar water

• salt

Multiple Choice

What is a compound

• sodium

• sugar

• nitrogen

• air

Multiple Choice

Why is water classified as a compound?

• Because it is an element, which consists of only one type of atom.

• Because it is a substance, which can easily be separated.

• Because it is a substance composed of two or more kinds of atoms bonded together.

• Because it is an unevenly mixed solution, or a heterogeneous mixture.

Multiple Choice

Which is the best estimate of the melting point of Rubidium (Rb)?

• 25* C

• 40* C

• 75* C

• 184* C

Multiple Choice

A student is designing an experiment for the science fair.  She needs to find a material that conducts an electric current, and her teacher has provided her with samples of the following elements.  Which of them should she choose?

• argon

• fluorine

• copper

• phosphorous

Multiple Choice

This is a chemical reaction for the decomposition of carbonic acid into water and carbon dioxide.

How does this reaction support the Law of Conservation of Mass?

• Several molecules of water are produced.

• The mass of carbon atoms is reduced during the reaction.

• The mass of the atoms in the reactant equals the mass of the atoms in the products.

• The mass of hydrogen atoms is the only thing that remains the same before and after the reaction.

Multiple Choice

The mass of the products in a chemical reaction is the same as the mass of the reactants in the reaction. Which law best describes this statement?

• The Law of Conservation of Angular Momentum

• The Law of Superposition

• The Law of Conservation of Matter

• The Law of Entropy

Multiple Choice

Which is classified as an element?

• carbon dioxide

• iron

• vinegar

• water

Multiple Choice

Which is an example of a chemical reaction?

• a pot of water boiling

• an iron nail rusting

• a piece of ice melting

• a sugar cube dissolving in tea

Multiple Choice

Which best describes the sequence o the elements in Period 5 of the periodic table?

• highly reactive gases, relatively non reactive metals, metalloids, very nonreactive gases, nonreactive nonmetals

• highly reactive metals, relatively nonreactive metals, metalloids, reactive nonmentals, reactive gases

• nonreactive gases, metalloids, nonreactive metals, highly reactive metals, highly reactive gases

• nonreactive gases, nonreactive metals, highly reactive metals, metalloids, reactive nonmetals, reactive gases

Multiple Choice

A scientist recognizes a white powder as sugar due to its white crystals and its sweet taste.  However, the scientist notices that the elements that make up the sugar - carbon, hydrogen, and oxygen - look nothing like sugar, nor are they sweet.  What is the best explanation for this?

• Sugar is a compound, and compounds usually have a different appear

• Sugar is an element, so its properties are unique.

• Sugar is a heterogeneous mixture, so its appearance is unique.

• Substances in nature change randomly and it is impossible to predict those changes.

Multiple Choice

Which statement is true about a chemical reaction?

• The physical states of the atoms in the reactants determine the products.

• Some of the atoms in the reactants will be a part of the products.

• The number of atoms in the reactants determines the products.

• All of the atoms in the reactants will be a part of the products.

Multiple Choice

Which example BEST represents an interconnection between an aquatic food web and a terrestrial food web?

• Fish eat insects that land on the surface of a pond.

• Snakes eat bird eggs.

• Bats eat mosquitos.

• Mountain lions catch and eat deer.

Multiple Choice

Chlorine has 7 valence electrons. With what group of elements will chlorine most readily bond?

• group 1

• group 2

• group 16

• group 18

Multiple Choice

Where is the majority of Earth's freshwater located?

• clouds

• Pacific Ocean

• polar ice caps

• rivers

Multiple Choice

Which is the best example of a chemical change?

• butter melting

• egg cooking

• paper tearing

• water evaporating

Multiple Choice

The population density of marine life is denser along the shorelines of the ocean than farther out in the deep waters of the ocean.  Which statement provides the BEST reason for this situation?

• Ocean currents prevent many smaller marine organisms from living in deep water.

• The shallow waters have fewer predators.

• Coastal waters are less polluted than the deeper waters of the ocean.

• There are more nutrients in shallow waters.

Multiple Choice

Which chemical equation best represents the Law of Conservation of Mass?

• $$H\ +\ O\ \rightarrow\ H_2O$$  
  

• $$H_2\ +\ O_2\ \rightarrow\ H_2O$$  

• $$2H_2\ +\ O_2\ \rightarrow\ 2H_2O$$  

• $$H_2\ +\ O_2\ \rightarrow\ 2H_2O_2$$  

Multiple Choice

Chemical $$X$$  has a mass of 5 grams, and chemical $$Y$$   has a mass of 10 grams. If the two chemicals are mixed and a complete chemical reaction takes place, what is MOST LIKELY the mass of the product?

• 5 grams

• 15 grams

• 10 grams

• 50 grams

Multiple Choice

In some environments, wolves prey on deer for their source of food. If all of the wolves were taken from the environment, what would most likely happen to the deer population?

• The deer population would increase and begin to compete for food.

• The deer population would become larger and healthier animals.

• The deer population would decrease, because there would be an increase in disease.

• The deer population would change color, because they would not have to hide from wolves.

Multiple Choice

How can a scientist, using the periodic table, find an element with properties similar to another element?

• by comparing density

• by finding its periodic group

• by comparing malleability

• by comparing atomic weight

Multiple Choice

How are mutualism and parasitism different?

• Both organisms benefit in mutualism, while in parasitism only one organism benefits at the other’s expense.

• Both organisms benefit in parasitism, while in mutualism only one organism benefits at the other’s expense.

• Both organisms benefit in mutualism, while in parasitism one organism benefits, and the other is neither harmed nor benefits.

• Both organisms benefit in parasitism, while in mutualism one organism benefits, and the other is neither harmed nor benefits.

Multiple Choice

Which is an example of a physical change?

• boiling

• burning

• rotting

• rusting

Multiple Choice

How are mutualism and parasitism different?

• Both organisms benefit in mutualism, while in parasitism only one organism benefits at the other’s expense.

• Both organisms benefit in parasitism, while in mutualism only one organism benefits at the other’s expense.

• Both organisms benefit in mutualism, while in parasitism one organism benefits, and the other is neither harmed nor benefits.

• Both organisms benefit in parasitism, while in mutualism one organism benefits, and the other is neither harmed nor benefits.

Multiple Choice

A scientist has a hypothesis that a large volcanic eruption caused a change in global temperature. Which information gained from ice cores is MOST useful in supporting the scientist's hypothesis?

• levels of dissolved oxygen

• identities of trace metals

• estimates of natural radioactivity

• amounts of atmospheric dust

Multiple Choice

What would have the greatest long-term impact on reducing the amount of carbon dioxide in the air?

• planting trees around a farm

• cutting down trees around a farm

• increasing the number of livestock on a farm

• decreasing the number of livestock on a farm

Multiple Choice

Which project is MOST LIKELY to interest a scientist working at a biotechnology company?

• study and reconstruction of fossilized bones

• conservation of key species within ecosystems

• development of genetically modified corn plants

• prevention of sewage leaking into water supplies

Multiple Choice

Which is the primary source of energy for most cells in the body?

• sugar

• fat

• protein

• vitamin

Multiple Choice

Which source of water pollution includes oil and gasoline discharge from automobiles and storm sewer discharge?

• agriculture

• sedimentation

• bacteria

• urban runoff

Multiple Choice

The table shows the food choices for two species of birds.

Which will most likely happen to Questors as a result of Wood Plaxers migrating to their habitat?

• The Questors will compete with the Wood Plaxers for food resources.

• The Questors will be forced to fly to a different habitat.

• The two species will become extinct.

• The two species will coexist with no competition.

Multiple Choice

Which BEST explains the importance of dissolved gases in the ocean?

• They help control pollution.

• They help provide oxygen for aquatic animals.

• They help maintain a constant water temperature.

• They help maintain constant levels of salinity.

Multiple Choice

What happens to most of the energy as it moves throughout a food web?

• It is changed into light energy.

• It is changed into heat energy.

• It is changed into mass.

• It is changed into decomposers.

Multiple Choice

Which BEST describes a bio-indicator?

• a species that has a short life span

• a species that depends on specific conditions to survive

• a species that can adapt to a variety of conditions

• a species that has been introduced to an ecosystem

Multiple Choice

Where do plants get the food they need for energy?

• They absorb it directly from the sun.

• They absorb it directly from the soil.

• They produce it during photosynthesis.

• They receive it from atmospheric gases.

Multiple Choice

What characteristic of aluminum allows it to be made into aluminum foil?

• It is dense.

• It is soluble.

• It is magnetic.

• It is malleable.

Multiple Choice

Which best represents the flow of energy within an aquatic ecosystem?

• algae → insects → fish → turtle → sunlight

• insects → algae → fish → turtle → sunlight

• sunlight → insects → algae → fish → turtle

• sunlight → algae → insects → fish → turtle

Multiple Choice

Which substance is composed of more than one element?

• water

• carbon

• gold

• sodium

Multiple Choice

A runner is preparing to run a long race. Which would provide the highest level of energy for the runner?

• minerals

• carbohydrates

• proteins

• vitamins

Multiple Choice

After a chemical reaction occurs in an open test tube, measurements indicate that the mass of the reactants is greater than the mass of the products remaining in the test tube.  What MOST LIKELY explains the measurements?

• A gas was produced.

• A solid was produced.

• The salinity of the reactants was high.

• The temperature of the reactants was low.

Multiple Choice

Why are digestion and respiration important to the body?

• They control the production of hormones in the body.

• They build muscle and bone that the body needs.

• They store food for the body.

• They help provide the energy needed for body functions.

Multiple Choice

Which best describes a method of obtaining energy that may cause changes in water temperature and harm to fish populations?

• burning coal

• using ethanol in cars

• installing solar panels on a home

• generating electricity in a hydroelectric power plant

Multiple Choice

Which is a nonrenewable resource?

• oil

• sunlight

• water

• wood

Multiple Choice

Which are most responsible for creating acid rain pollution?

• nuclear power plants

• coal-burning power plants

• hydroelectric power plants

• wood-burning power plants

Multiple Choice

The table shows the estimated energy production (in quadrillions of BTUs) from fossil fuels over a 20-year period.

Which conclusion is best supported by the data?

• Dependency on oil has increased, therefore energy production from oil is increasing.

• Dependency on oil has increased, therefore energy production from natural gas is decreasing.

• Dependency on coal has increased, therefore energy production from coal is increasing.

• Dependency on coal has increased, therefore energy production from natural gas is decreasing.

Multiple Choice

Which is most likely a major concern associated with burning fossil fuels?

• Burning fossil fuels can pollute the oceans.

• Burning fossil fuels can remove harmful chemicals from precipitation.

• Burning fossil fuels can remove carbon dioxide from the atmosphere.

• Burning fossil fuels can produce smog, which can cause respiratory illnesses.

Multiple Choice

Which action shows concern for the environment with regards to the resources of the oceans?

• developing technology which will allow for an increase in fish harvesting.

• allowing factories to release untreated wastewater into the oceans

• filling in oceanfront wetlands in order to extend beachfront properties

• setting limits on fish harvesting in the oceans

Multiple Choice

How owuld a large increase in the salinity of an estuary most likely affect the ecosystem of the estuary?

• All organisms would die.

• All organisms would continue to live as they now do.

• The number of salt-tolerant organisms would increase, and the number of salt-intolerant organisms would decrease.

• The number of salt-intolerant organisms would increase, and the number of salt-tolerant organisms would decrease.

Multiple Choice

Which would indicate the water in a lake is not safe for drinking?

• many varieties of fish in the lake

• high dissolved-oxygen levels in the lake

• cold water temperature of the lake

• high turbidity levels in the lake

Multiple Choice

Which best explains why all of the Earth’s freshwater is not available for human use?

• Most of Earth’s freshwater is only in lakes.

• Most of Earth’s freshwater is underground.

• Most of Earth’s freshwater is still in the water cycle.

• Most of Earth’s freshwater is frozen water

Multiple Choice

How can upwellings improve fishing for ocean fishermen?

• They cause the ocean water to get warmer.

• They cause ocean currents to remain calm.

• They bring nutrients from the cold, deep ocean waters

• They bring ocean currents from the equator.

Multiple Choice

If a lake has excess levels of phosphates and nitrates in its water, what will most likely result?

• The temperature of the lake water will decrease.

• The turbidity levels of the lake will decrease.

• The dissolved-oxygen levels in the lake will increase.

• The growth of algae in the lake will increase.

Multiple Choice

What effect does the water cycle have on the total amount of water on Earth?

• The total amount of water on Earth is constantly increasing.

• The total amount of water on Earth is constantly decreasing.

• The total amount of water on Earth remains relatively constant.

• The total amount of water on Earth changes due to periods of global warming and cooling.

Multiple Choice

Which characteristic of water quality provides the most information regarding the health of a water system?

• clarity

• temperature

• concentration of heavy metals

• presence of indicator species

Multiple Choice

Where is most of Earth’s freshwater located?

• in the clouds

• in the ice caps

• in the ocean

• in the ground

Multiple Choice

A geologist identifies the identical index fossils in rock layers from two different areas. Which conclusion is best supported by this discovery?

• The deposition rate of the two rock layers was identical.

• The fossil organism evolved independently in the two separate areas.

• The two rock layers were deposited at approximately the same time.

• The index fossil will also occur in sediment deposited on top of these rock layers.

Multiple Choice

Which supports the theory that some mountains were once at the bottom of an ocean?

• There are underwater mountains on the ocean floor today.

• Freshwater rivers flow to the ocean.

• Fossils of marine organisms are found on the tops of some mountains.

• Both mountains and ocean floors have similar minerals in their rocks.

Multiple Choice

Which evidence supports the idea that life on Earth has continually evolved?

• evidence from layers of tree rings

• evidence from rock layers, fossils, and ice cores

• evidence gathered from melting glaciers

• evidence that the climate has changed over the past 100 years

Multiple Choice

Which would most likely increase the genetic variation in a population of organisms?

• increase in diseases

• decrease in diseases

• increase in mutations

• decrease in mutations

Multiple Choice

Which is the most accurate method scientists use to predict the age of Earth?

• relative dating of rock layers

• radioactive dating of rocks

• comparing the ages of different fossils

• investigating core samples from the Arctic

Multiple Choice

Which is the best reason for scientists to study ice cores obtained from Earth’s ice caps?

• to evaluate potential oil drilling sites

• to study the quality of water stored in glaciers

• to determine the rate of melting in polar regions

• to study past climates by analyzing trapped gases and particles

Multiple Choice

Which is the best evidence for evolution?

• new rock layers containing fossils of simple organisms

• new rock layers containing fossils unlike existing organisms

• old rock layers containing fossils unlike existing organisms

• old rock layers containing fossils of complex organisms

Multiple Choice

Which best explains why mammals became dominant after the mass extinction of the dinosaurs?

• They had traits that helped them adapt to environmental changes.

• They were larger than dinosaurs and ate different foods.

• They lived in different areas on Earth than dinosaurs.

• They were able to hibernate for thousands of years.

Multiple Choice

Which demonstrates how genetic variation may result from a change in the environment where an animal lives?

• A salmon swims faster as it enters colder waters.

• A snake increases its body temperature because it moves on top of a rock in direct sunlight.

• A beetle stands out to predators because it moves among plants that have colors different than its own.

• An arctic fox changes its color over time because it migrates to an area with a different climate.

Multiple Choice

Which is the most accurate way of determining the age of a fossil?

• radioactive dating

• relative dating

• dating index fossils

• dating the rock layers above the fossil

Multiple Choice

Which allows scientists to investigate what Earth’s climate was like over the past 740,000 years?

• volcanic deposits

• fossils

• faults

• ice cores

Multiple Choice

Which best describes uniformitarianism?

• The time it takes for erosion to occur has changed since Earth first formed.

• The movement of the continents no longer occurs because of changes in ocean currents.

• The processes that shape the Earth continue as they have since the Earth formed.

• The formation of rock layers has slowed because humans have altered the environment.

Multiple Choice

If a bat, an alligator, and a bird evolved from a common ancestor, what most likely can be concluded?

• They have similar anatomical structures.

• They live in the same part of the world.

• They are in the same biological classification.

• They are able to survive changes in their environments.

Multiple Choice

Recent changes in species can be found in the upper layers of rock. This provides a link between which two scientific ideas?

• cell theory and the theory of evolution

• the periodic nature of the elements and cell theory

• the theory of evolution and the Law of Superposition

• the Law of Superposition and the periodic nature of the elements

Multiple Choice

Which of these would most likely happen to a species that is not able to adapt to a changing environment?

• The species would become extinct over time.

• The species would develop mutated cells.

• The species would develop resistance to disease.

• The species would change the environment.

Multiple Choice

Which statement supports the theory of evolution?

• All living cells come from previous cells.
• All plants and animals have DNA.
• Matter cannot be created or destroyed during chemical reactions.
• Fossils provide evidence that vertebrates share a common ancestor.

Multiple Choice

Which example BEST represents an interconnection between an aquatic food web and a terrestrial food web?

• Fish eat insects that land on the surface of a pond.
• Snakes eat bird eggs.
• Bats eat mosquitos.
• Mountain lions catch and eat deer.

Multiple Choice

What is one way the government of the United States attempts to reduce pollution in the oceans?

• create new desalination plants
• discontinue sewage treatment programs
• increase oil and gasoline production
• enforce laws limiting trash dumping

Multiple Choice

The population density of marine life is denser along the shorelines of the ocean than farther out in the deep waters of the ocean.  Which statement provides the BEST reason for this situation?

• Ocean currents prevent many smaller marine organisms from living in deep water.
• The shallow waters have fewer predators.
• Coastal waters are less polluted than the deeper waters of the ocean.
• There are more nutrients in shallow waters.

Multiple Choice

Which is an example of a physical change?

• boiling
• burning
• rotting
• rusting

Multiple Choice

A scientist has a hypothesis that a large volcanic eruption caused a change in global temperature. Which information gained from ice cores is MOST useful in supporting the scientist's hypothesis?

• levels of dissolved oxygen
• identities of trace metals
• estimates of natural radioactivity
• amounts of atmospheric dust

Multiple Choice

Which project is MOST LIKELY to interest a scientist working at a biotechnology company?

• study and reconstruction of fossilized bones
• conservation of key species within ecosystems
• development of genetically modified corn plants
• prevention of sewage leaking into water supplies

Multiple Choice

Which source of water pollution includes oil and gasoline discharge from automobiles and storm sewer discharge?

• agriculture
• bacteria
• sedimentation
• urban runoff

Multiple Choice

Which BEST describes a bio-indicator?

• a species that has a short life span
• a species that depends on specific conditions to survive
• a species that can adapt to a variety of conditions
• a species that has been introduced to an ecosystem

Multiple Choice

What characteristic of aluminum allows it to be made into aluminum foil?

• It is dense.
• It is soluble.
• It is magnetic.
• It is malleable.

Multiple Choice

Which pure substance is composed of more than one element?

• water
• carbon
• gold
• sodium