7th Grade Science Test: The Nature of Matter

Do Not Write On This Document—Record your answers on your Answer Document.

1. Which of the following is a physical property of an element?

a. size

b. ability to rust

c. flammability

d. ability to tarnish

2. A cubic centimeter is a unit for measuring

a. length.

b. volume.

c. mass.

d. density.

3. Which of the following is NOT a characteristic of a compound?

a. has different properties from the elements that formed it

b. pure substance made of two or more elements

c. different samples have different properties

d. can be represented by a chemical formula

4. A measurement of the amount of matter in an object is its

a. mass.

b. density.

c. volume.

d. length.

5. A(n) _____ is an example of a homogeneous mixture that is very evenly mixed.

a. compound

b. element

c. pure substance

d. solution

6. A chemical bond is

a. a group of atoms that are joined together.

b. the basic particle of matter.

c. the force that holds two atoms together.

d. a substance formed from the chemical combination of two or more atoms.

7. Which of the following is an example of a chemical change?

a. melting butter

b. mixing milk and chocolate syrup

c. breaking glass

d. burning fuel

8. Group of the same or different atoms held together by chemical bonds.

a. mixture

b. molecule

c. solution

d. precipitate

9. The change from a liquid to gas is called

a. evaporation.

b. condensation.

c. melting.

d. sublimation.

10. A substance which quickly takes up the shape and volume of its container is a

a. solid.

b. liquid.

c. gas.

d. crystal.

11. An element's _____ shows the number of protons in its nucleus.

a. atomic mass

b. atomic number

c. chemical symbol

d. period

12. Dmitri Mendeleev created the first

a. chemical reaction.

b. metal alloy.

c. periodic table.

d. semiconductor.

13. The particles in the nucleus of an atom which have no charge are called

a. electrons.

b. ions.

c. neutrons.

d. protons.

14. A change in matter that produces new substances is called a

a. chemical reaction.

b. physical change.

c. mixture.

d. solution.

15. Which of the following is an example of a physical property?

a. chemical composition

b. ability to burn

c. freezing point

d. ability to react with metals

16. A chemical reaction in which energy is absorbed in the form of heat is called

a. synthetic.

b. exothermic.

c. combustion.

d. endothermic.

17. Chemical equations must be balanced because chemical reactions obey the law of

a. activation.

b. conservation of mass.

c. decomposition.

d. mass coefficients.

18. When two or more substances combine to form a more complex substance, the process is called a

a. decomposition reaction.

b. replacement reaction.

c. synthesis reaction.

d. physic al change.

19. The number in front of a chemical formula that tells how many molecules or atoms of each reactant take part in a reaction is called a

a. symbol.

b. subscript.

c. coefficient.

d. concentration.

20. Which of the following is an example of a chemical change?

a. meat spoiling

b. water freezing

c. mercury rising

d. butter softening

21. Which is true about an exothermic reaction?

a. It releases energy.

b. It absorbs energy.

c. It requires no activation energy.

d. The energy of the products is greater than the energy of the reactants.

22. All matter is made of

a. atoms.

b. compounds.

c. particulates.

d. miniature Lego-like structures.

23. Crude oil undergoes a process called ____ which separates out various substances, like gasoline and kerosene, that can be used as fuels.

a. filtration

b. magnetic attraction

c. distillation

d. precipitation.

Matching. Choose the letter of the term in the word box which best completes each of the following definitions. Record on your Answer Document.

A. element B. volume C. density D. compound E. valence

24. Pure substance made of two or more different kinds of atoms chemically combined.

25. Mass divided by volume.

26. The outer-most electrons that surround an atom's nucleus.

27. A pure substance that cannot be broken down into any other substances by chemical means.

28. How much space an object occupies.

True or False. Fill in A if the statement is true; B if the statement is false. Record on your Answer Document.

29. A chemical equation shows a chemical reaction using symbols instead of words.

30. The reactants are the new materials produced during a chemical reaction and are on the right side of a chemical equation.

31. A solid block that sinks in a container of water has a lower density than water.

32. Ice is water in a liquid phase.

33. A mixture has two or more substances held together in the same place, but they do not chemically combine.

34. Coffee and milk are examples of homogeneous mixtures called solutions.

35. Weight is a measure of matter.

Use the equation below to answer questions 36, 37, and 38.

LiHClH2LiCl

36. How many atoms of hydrogen (H) are on each side of the chemical equation above?

a. one on each side

b. one in the reactants and two in the products

c. two on each side

37. Which shows a balanced equation for the chemical equation above?

a. 3Li + HCLH2 + 2LiCl

b. Li + 2HCLH2 + LiCl

c. 2Li + 2HCLH2 + 2LiCl

38. What kind of chemical reaction is shown in the equation above?

a. synthesis

b. decomposition

c. replacement

Use the diagram below to answer questions 39 and 40.

39. The chemical symbol for phosphorus is

a. 15.

b. P.

c. Sb.

40. Bismuth has an atomic number of

a. 15.

b. 33.

c. 83.

Use the diagram below to answer questions 41 and 42 .

41. The part of an atom labeled B is a(an)

a. proton.

b. neutron.

c. electron.

42. The part of an atom that is lost, gained, or shared in a chemical reaction, and has a negative charge, is the part labeled

a. A.

b. B.

c. C.

The test tube below has three different liquids: water, corn syrup, and cooking oil. Use the diagram below to answer questions 43, 44, and 45.

Liquid A

Liquid B

Liquid C

43. Look at the diagram. Which liquid is the least dense?

a. Liquid A

b. Liquid B

c. Liquid C

44. Look at the diagram. Which liquid is the most dense?

a. Liquid A

b. Liquid B

c. Liquid C

45. What is the density of the cooking oil if 10 grams has a volume of 10.8 cm3?

a. 108 g/cm3

b. 1.08 g/cm3

c. 0.926 g/cm3

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