Mid Year 8th Grade Science Exam

1. A group of parts that work together is called a ...

Technology

System

Process

Feedback

2. Prototypes are used to ....

Patent an invention.

Test the operation of a product.

Identify a need.

Research a problem.

3. How would you calculate the density of an object?

Divide its weight by its volume.

Divide its mass by its volume.

Multiply its volume times its mass.

Multiply its weight times its mass.

4. In the laboratory, volumes of liquid are usually measured with a(n).....

Electrode

Scale

Triple beam balance

Graduated cylinder

5. One useful tool that may help a scientist interpret data by revealing unexpected patterns is a ....

Variable

Graph

Theory

Law

6. Acids are described as corrosive because they....

Turn litmus blue

Taste bitter.

"eat away" at other materials.

Feel slippery

7. Anything that has mass and takes up space is called...

Matter

Energy

Heterogeneous

Homogeneous

8. What is the greatest number of valence electrons an atom can have?

2

3

8

12

9. During an experiment, which factors must be controlled so that researchers can draw a logical conclusion from the experiment?

Variables

Operational definitions

Inquiries

Theories

10. When scientists create a representation of a complex process, they are ....

Inferring

Predicting

Classifying

Making models

11. During an experiment, if you purposely change the temperature to test a hypothesis, the temperature is called the...

Manipulated variable.

Responding variable.

Operational variable.

Dependent variable.

12. The energy of matter in motion is called....

Kinetic energy

Potential energy

Chemical energy

Electromagnetic energy

13. How many meters are there in a kilometer?

10

100

1000

10,000

14. What is the first thing you should do if an accident occurs?

Find the emergency equipment.

Notify the teacher.

Go to the nearest hospital.

Start first aid treatment.

15. Which of the following is a valid reason why a scientist might reject a scientific theory?

Some people disagree with it.

It covers too broad a topic.

New evidence contradicts it.

It is too old.

16. Choose Option 1-Free Gift

Option 1

Option 2

Option 3

Option 4

17. Because atoms are so small.....

Scientists create models to describe them.

They can not be made of smaller particles.

There is no way to describe them.

They cannot be synthesized by scientists.

18. From an element's location in the periodic table, you can predict...

Its properties.

Its chemical name.

Its chemical symbol.

When it was discovered.

19. What is the chemical name for the compound with the formula Na₂ S ?

Sodium fluoride

Magnesium sulfide

Lithium oxide

Sodium sulfide

20. The metric system of measurement is based on the number ....

1

10

12

100

21. Chemistry is....

A characteristic of a substance that can be observed without changing the substance into another substance.

The study of matter and how matter changes.

Anything that has mass and takes up space.

A rapid reaction between oxygen and a substance called a fuel.

22. Which of these statements about a column of the periodic table is true?

The elements have similar properties.

The elements have a wide range of properties.

The elements have the same atomic number.

The elements have the same atomic mass.

23. An ionic bond is the attraction between....

Similarly charged ions.

Oppositely charged ions.

Neutral ions.

Neutral atoms.

24. An engineer is a.....

Person who studies plants.

Person trained to use both technological and scientific knowledge to solve practical problems.

Possible explanation for a set of observations or answer to a scientific question.

25. A chemical reaction that absorbs energy in the form of heat is described as

Endothermic

Exothermic

Combustion

Unbalanced

26. Ions that are made of more than one atom are examples of ....

Polyatomic ions

Negative ions

Positive ions.

Neutral ions.

27. CaCO₃represents a chemical…..

Symbol

Formula

Subscript

Reaction

28. In the periodic table, the most reactive metals are found ....

In Group 1, the first column on the left.

In Period 1, the first row across the top.

In Groups 13 through 16 in the center.

In Periods 6 and 7 at the bottom.

29. Observations that deal with a number or amount are called...

Manipulated observations.

Quantitative observations.

Qualitative observations.

Operational observations.

30. The measurement of how much mass is contained in a given volume is called...

Weight

Melting point

Boiling point

Density

31. Which is a characteristic property of acids?

They turn blue litmus paper red.

They turn red litmus paper blue.

They taste bitter.

They do not react with metals.

32. A summary of what you have learned from a scientific experiment is called a(n)....

Hypothesis

Inquiry

Conclusion

Law

33. When an atom loses an electron, it becomes a ....

Positive ion.

Negative ion.

Neutral ion.

Neutral atom.

34. The density of a block of wood with a volume of 50 cubic centimeters and a mass of 100 grams is

2 g/cubic centimeter

0.5 g/cubic centimeter

500g/cubic centimeter

5,000g/cubic centimeter

35. Which of the following is a characteristic property of ionic compounds?

They have low melting points.

They have low boiling points.

They form hard, brittle crystals with characteristic shapes.

They contain no charged particles.

36. How do liquid water, ice, and water vapor differ from each other?

They are different states of matter.

They are different compounds.

They are made of different kinds of molecules.

They are made of different kinds of atoms.

37. Which stage of the scientific process enables a scientist to check the work of other scientists?

Classifying

Concluding

Hypothesizing

Communicating

38. Using one or more of your senses to gather information is called....

Observing.

Inferring.

Predicting.

Classifying.

39. In science, a hypothesis must be

Correct

Manipulated

Controlled

Testable

40. Soil, a salad, and sugar water are all examples of ....

Elements

Compounds

Mixtures

Atoms

41. The factor that may change in response to the manipulated variable is called the...

Hypothetical variable

Responding variable

Operational variable

Independent variable

42. One example of a chemical change is...

Filtering.

Burning wood.

Boiling water.

Crushing a can.

43. You can find the pH of a substance by using...

Plain paper

A thermometer.

Litmus indicator.

A conductivity tester.

44. What is the goal of technology?

To produce and deliver cereal.

To understand how the natural world functions.

To study the natural world.

To improve the way people live.

45. A chemical equation that shows the same number of each kind of atom on both sides of the equation is said to be...

Balanced.

Unbalanced.

An incomplete reaction.

A replacement reaction.

46. When scientists put things into categories or group together items that are alike in some way, they are ....

Inferring

Predicting

Classifying

Making models

47. What happens when chemical bonds break and new bonds form?

A physical change

A chemical reaction

Matter is destroyed

Surface area increases

48. The elements in a column of the periodic table ...

Have similar properties.

Are in the same period.

Have the same atomic mass.

Have very similar chemical symbols.

49. H₂O, CO₂, and C₁₂H₂₂O₁₁ are all examples of chemical…

Properties.

Changes.

Bonds.

Formulas.

50. Which of the following terms means that metals can be pulled into thin strands or wires.

Polar

Alloy

Ductile

Malleable

51. Electrons involved in bonding between atoms are...

Valence electrons.

Inside the nucleus.

Closest to the nucleus.

Positively charged.

52. Explaining or interpreting the things you observe based on reasoning from what you already know is called...

Observing

Inferring

Predicting

Classifying

53. A row across the periodic table is called a ....

Group

Family

Section

Period

54. If you heat a liquid and measure the temperature at which it boils, you are measuring a(n)...

Atomic property

Physical property

Chemical property

Molecular property

55. Making a forecast of what will happen in the future based on past experience or evidence is called...

Observing

Inferring

Predicting

Classifying

56. In water, bases form ...

Hydroxide ions.

Hydrogen ions.

Hydrogen gas.

Oxide ions.

57. In a scientific experiment, the responding variable can also be called the ...

Operational variable

Manipulated variable

Dependent variable

Independent variable.

58. Which group contains the most elements?

Metalloids

Non metals

Metals

Transition elements

59. A covalent bond in which electrons are shared unequally is...

Polar

A double bond.

Ionic.

Polyatomic.

60. To calculate the density of an object, you would....

Divide its mass by its length

Divide its mass by its volume.

Divide its volume by its mass.

Multiply its mass by its volume.

61. What can you tell about methane (CH₄) from its molecular formula?

It contains four carbon atoms.

It contains one hydrogen atom.

It contains four hydrogen atoms.

It forms groups of four molecules.

62. Mass and weight are different because...

Mass depends on the force of gravity.

Weight depends on the force of gravity.

Weight depends on the amount of matter an object contains.

Mass does not depend on the amount of matter an object contains.

63. Science and technology are...

The same thing.

Not important.

Dependent on each other.

Completely unrelated.

64. Which particles in atoms have a negative electric charge?

Electrons

Protons

Neutrons

Nuclei

65. The basic unit of length in the metric system is the ...

Foot

Meter

Mile

Kilometer

66. What holds atoms together in a molecule?

Density.

Gravity.

Physical bonds.

Chemical bonds.

67. The number placed below an element's symbol in a chemical formula is called a ...

Subscript

Coefficient

Reactant

Product

68. Fireworks exploding in the sky and giving off light are an example of a(n)..

Endothermic change.

Exothermic change.

Physical change.

Change in mass.

69. Table sugar and table salt are examples of

Atoms.

Elements.

Mixtures.

Pure substances.

70. If a shoe box measures 6 cm high, 7 cm wide, and 20 cm long, what is its volume?

420 centimeters

420 cubic centimeters

840 cubic centimeters

840 centimeters

71. Which is a likely use for a base?

As a vitamin in your food

Etching metals for printing

Making foods taste sour

Making soaps and detergents

72. A line graph shows...

Changes in the responding variable only

Changes in the manipulated variable only

How the responding variable changes in response to the manipulated variable.

How the manipulated variable changes on its own.

73. Normal rainfall is slightly acidic, which means its pH must be...

Less than 2.

Between 5-7.

Between 2-4.

Between 7-9.

74. How many chemical bonds can each carbon atom form?

One

Two

Three

Four

75. A possible explanation for a set of observations or answer to a scientific question is called a(n)....

Prediction.

Hypothesis

Theory

Law.

76. Each family in the periodic table has its own characteristic properties based on the number of ...

Neutrons

Valence electrons

Protons

Ions

77. Which of the following is NOT an example of a chemical change?

Gas burning on a stove

Rust forming on an iron fence

Salt dissolving in a glass of water

Using electricity to break down water into hydrogen and oxygen

78. Observations that deal with descriptions that cannot be expressed in numbers are called...

Manipulated observations.

Quantitative observations.

Qualitative observations.

Operational observations.

79. Which particles in an atom are in the nucleus?

Protons and neutrons

Protons and electrons

Protons and ions

Electrons and neutrons

80. Most metals are NOT...

Ductile

Good conductors of heat and electricity

Liquid at room temperature

Malleable

81. Carbon is able to bond with atoms of other elements in many different ways because it has....

6 protons.

4 electrons.

6 valence electrons.

4 valence electrons.

82. If you describe methane as a gas that easily catches fire, you are describing a ....

State of matter

Physical property

Chemical property

Chemical formula

83. One example of a physical change is...

Burning paper.

Baking cookies.

Heating table sugar.

Dissolving salt in water.

84. The pH scale measures....

The strength of an acid.

The strength of hydrogen ions.

The concentration of hydrogen ions.

The concentration of an acid.

85. The most important lab safety rule is...

Always wear a lab apron.

Always wear safety goggles.

Design and conduct your own experiments without asking your teacher.

Always follow your teacher's instructions and textbook directions exactly.

86. The atomic number of an element is based on the ....

Mass of its nucleus.

Number of electrons around its core.

Number of protons in its nucleus.

Number of neutrons in its nucleus.

87. A chemical bond formed when two atoms share electrons is called a(n)...

Ionic bond

Covalent bond

Polyatomic bond.

Crystal bond.

88. Which parts of the atom move around the nucleus?

Atomic mass units

Electrons

Protons

Neutrons

89. The volume of an irregular object can be measured by...

Multiplying the object's length, width and height.

Dividing the object's density by its mass.

Submerging the object in water in a graduated cylinder.

Placing the object on a triple-beam balance.

90. What is a double bond?

A bond between two atoms.

One pair of electrons shared between two atoms.

Two pairs of electrons shared between two atoms.

Two pairs of electrons shared between four atoms.

91. The first step in designing or redesigning a product is...

Thinking about ways to solve the problem.

Deciding what needs you are trying to meet.

Building a prototype.

Fully researching the problem.

92. In a water solution, how do acids differ from bases?

Acids form hydrogen ions, while bases form hydroxide ions.

Acids turn litmus blue, while bases turn litmus red.

Acids form salts, but bases do not.

Hydrogen ions remain dissolved, but hydroxide ions do not.

93. A well-tested explanation for a wide range of observations or experimental results is called a scientific...

Inquiry.

Hypothesis.

Theory.

Law.

94. A metal washer has a mass of 0.27g and a volume of 0.1 cubic centimeters. What is its density?

0.027 g/cubic centimeter

0.037 g/cubic centimeter

2.7 g/cubic centimeter

2.7 g/square centimeter

95. The amount of space an object takes up is its...

Volume

Density

Mass

Length

96. Ionic compounds are electrically...

Charged.

Positive.

Negative.

Neutral.

97. The kilogram is the basic metric unit of....

Length

Mass

Weight

Volume

98. In an atom, the number of protons equals the number of...

Nuclei

Electrons

Neutrons

Isotopes

99. Which of the following is a balanced chemical equation?

H2O-→H2O + O2

2Fe2O3 + 3C→ 4Fe + 3CO2

SO2 + O2+ 2H2O → 4H2SO4

2Mg +HCl → MgCl2 + H2

100. Which is the correct chemical equation for the following statement? Sodium reacts with oxygen in a 2 to 1 ration to produce sodium oxide.

2Na + O2 → Na2O

Na2O → 2 Na + O2

Na2O + O2→ 2Na

Na2 + O2→ 2NaO

Mid Year 8th Grade Science Exam

1. A group of parts that work together is called a ...

2. Prototypes are used to ....

3. How would you calculate the density of an object?

4. In the laboratory, volumes of liquid are usually measured with a(n).....

5. One useful tool that may help a scientist interpret data by revealing unexpected patterns is a ....

6. Acids are described as corrosive because they....

7. Anything that has mass and takes up space is called...

8. What is the greatest number of valence electrons an atom can have?

9. During an experiment, which factors must be controlled so that researchers can draw a logical conclusion from the experiment?

10. When scientists create a representation of a complex process, they are ....

11. During an experiment, if you purposely change the temperature to test a hypothesis, the temperature is called the...

12. The energy of matter in motion is called....

13. How many meters are there in a kilometer?

14. What is the first thing you should do if an accident occurs?

15. Which of the following is a valid reason why a scientist might reject a scientific theory?

16. Choose Option 1-Free Gift

17. Because atoms are so small.....

18. From an element's location in the periodic table, you can predict...

19. What is the chemical name for the compound with the formula Na2 S ?

20. The metric system of measurement is based on the number ....

21. Chemistry is....

22. Which of these statements about a column of the periodic table is true?

23. An ionic bond is the attraction between....

24. An engineer is a.....

25. A chemical reaction that absorbs energy in the form of heat is described as

26. Ions that are made of more than one atom are examples of ....

27. CaCO3 represents a chemical…..

28. In the periodic table, the most reactive metals are found ....

29. Observations that deal with a number or amount are called...

30. The measurement of how much mass is contained in a given volume is called...

31. Which is a characteristic property of acids?

32. A summary of what you have learned from a scientific experiment is called a(n)....

33. When an atom loses an electron, it becomes a ....

34. The density of a block of wood with a volume of 50 cubic centimeters and a mass of 100 grams is

35. Which of the following is a characteristic property of ionic compounds?

36. How do liquid water, ice, and water vapor differ from each other?

37. Which stage of the scientific process enables a scientist to check the work of other scientists?

38. Using one or more of your senses to gather information is called....

39. In science, a hypothesis must be

40. Soil, a salad, and sugar water are all examples of ....

41. The factor that may change in response to the manipulated variable is called the...

42. One example of a chemical change is...

43. You can find the pH of a substance by using...

44. What is the goal of technology?

45. A chemical equation that shows the same number of each kind of atom on both sides of the equation is said to be...

46. When scientists put things into categories or group together items that are alike in some way, they are ....

47. What happens when chemical bonds break and new bonds form?

48. The elements in a column of the periodic table ...

49. H2O, CO2, and C12H22O11 are all examples of chemical…

50. Which of the following terms means that metals can be pulled into thin strands or wires.

51. Electrons involved in bonding between atoms are...

52. Explaining or interpreting the things you observe based on reasoning from what you already know is called...

53. A row across the periodic table is called a ....

54. If you heat a liquid and measure the temperature at which it boils, you are measuring a(n)...

55. Making a forecast of what will happen in the future based on past experience or evidence is called...

56. In water, bases form ...

57. In a scientific experiment, the responding variable can also be called the ...

58. Which group contains the most elements?

59. A covalent bond in which electrons are shared unequally is...

60. To calculate the density of an object, you would....

61. What can you tell about methane (CH4) from its molecular formula?

62. Mass and weight are different because...

63. Science and technology are...

64. Which particles in atoms have a negative electric charge?

65. The basic unit of length in the metric system is the ...

66. What holds atoms together in a molecule?

67. The number placed below an element's symbol in a chemical formula is called a ...

68. Fireworks exploding in the sky and giving off light are an example of a(n)..

69. Table sugar and table salt are examples of

70. If a shoe box measures 6 cm high, 7 cm wide, and 20 cm long, what is its volume?

71. Which is a likely use for a base?

72. A line graph shows...

73. Normal rainfall is slightly acidic, which means its pH must be...

74. How many chemical bonds can each carbon atom form?

75. A possible explanation for a set of observations or answer to a scientific question is called a(n)....

76. Each family in the periodic table has its own characteristic properties based on the number of ...

77. Which of the following is NOT an example of a chemical change?

78. Observations that deal with descriptions that cannot be expressed in numbers are called...

79. Which particles in an atom are in the nucleus?

19. What is the chemical name for the compound with the formula Na₂ S ?

27. CaCO₃represents a chemical…..

49. H₂O, CO₂, and C₁₂H₂₂O₁₁ are all examples of chemical…

61. What can you tell about methane (CH₄) from its molecular formula?