1. STANDARD 5a
Students know reactant atoms and molecules interact to form products with different chemical properties

2. CHEMICAL REACTIONS
The reactants are the atoms and molecules that start a chemical change or reaction
The new substances that form in a chemical change are called products
During a chemical change or reaction, atoms in the reactants rearrange as chemical bonds break and new bonds form
The products of a chemical reaction have different chemical and physical properties than the reactants

3. CHEMICAL REACTIONS 55. The reactants of a chemical reaction have
A chemical properties identical to the products
B chemical properties different from the products
C the same chemical makeup as the products
D no chemical bonds
ANSWER: B

4. CHEMICAL REACTIONS
56. Which is evidence that a chemical reaction might have occurred?
A release of energy
B change in shape
C similarities in physical properties
D presence of ions
ANSWER: A

5. CHEMICAL REACTIONS
57. Which of the following statements is true about the reaction shown in the diagram?
A The products are identical to the reactants
B The atoms of the product rearrange to form new molecules
C The atoms of the reactants rearrange to form new molecules
D No chemical bonds are broken
ANSWER: C

6. STANDARD 5b
Students know the idea of atoms explains the conservation of matter: in chemical reactions the number of atoms stays the same no matter how they are arranged, so their total mass stays the same

7. CONSERVATION OF MATTER
Conservation of matter states that during a chemical reaction, matter is neither created nor destroyed
The total number of atoms stays the same before and after the reaction

8. CONSERVATION OF MATTER
58. According to the principle of the conservation of matter
A reactants have the same mass as the products
B reactants have more mass than the products
C products have less mass than the reactants
D products have more mass than the reactants
ANSWER: A

9. CONSERVATION OF MATTER
59. Which equation shows that the total mass during a chemical reaction stays the same?
A 1
B 2
C 3
D 4
ANSWER: C

10. CONSERVATION OF MATTER
N2O5 + H2O → HNO3
60. Berta wants to balance the equation shown above. Which number should she place in front of HNO3 in order to balance the equation?
A 1
B 2
C 3
D 4
ANSWER: B

11. Chemical Reactions
61. According to the law of conservation of mass, what mass of O2 is generated?
A 8 g
B 16 g
C g
D g
ANSWER: B

12. STANDARD 5c
Students know chemical reactions usually liberate heat or absorb heat

13. CHEMICAL REACTIONS
If a chemical reaction results in the release of energy, the reaction is called an exothermic reaction
This energy is often released as heat and light into the surroundings, which becomes warmer
If a chemical reaction results in a net absorption of energy, the reaction is called an endothermic reaction
The energy for the reaction is usually absorbed from the surroundings, which becomes cooler

14. CHEMICAL REACTIONS
The graphs show energy changes in endothermic and exothermic reactions.
The “bump” in the graph represents the activation energy, which is the minimum amount of energy required to get the reaction started
Exothermic Reaction
Endothermic Reaction

15. CHEMICAL REACTIONS 62. Burning wood is an exothermic reaction because
A energy is absorbed
B energy is released
C the reaction requires energy to keep going
D Activation energy is not required
ANSWER: B

16. CHEMICAL REACTIONS 63. In an endothermic reaction,
A the products give off heat
B mass is not conserved
C the products have less energy than the reactants
D the products have more energy than the reactants
ANSWER: D

17. CHEMICAL REACTIONS
64. The graphs show the energy changes that occur during a chemical reaction. Which graph best describes a chemical reaction that absorbs energy?
ANSWER: D

18. CHEMICAL REACTIONS
65. Which of the following is true of both exothermic and endothermic reactions?
A They absorb heat
B They release heat
C They require some energy to start
D They use more energy than they produce
ANSWER: C

19. STANDARD 5d
Students know physical processes include freezing and boiling, in which a material changes form with no chemical reaction

20. PHYSICAL CHANGES
A physical change differs from a chemical change in that chemical bonds are neither broken nor formed
The appearance of the substance will change, but not its chemical makeup
When water changes from a liquid to a solid, the appearance changes, but the ice and liquid water have the same chemical formula: H2O

21. Chemical Reactions
Freezing, melting and boiling are NOT chemical reactions. They are physical changes.

22. PHYSICAL CHANGES
A mixture is made of two or more substances that are together in the same place but are not chemically combined: salad, pizza
Making a mixture is a physical change because the parts of the mixture can be separated
A solution is a uniform mixture that has the same properties throughout: salt water

23. PHYSICAL CHANGES 66. A change of state is a physical change because
A the parts of the mixture can be separated
B the atoms of the substance form new chemical bonds
C the boiling point of the substance changes
D the chemical makeup of the substance stays the same
ANSWER: D

24. PHYSICAL CHANGES
67. David stirs a spoonful of sugar into a glass of lemonade. As he stirs, the sugar disappears. What type of change is occurring?
A chemical change
B creation of matter
C destruction of matter
D physical change
ANSWER: D

25. PHYSICAL CHANGES A physical change B chemical change
68. During boiling, liquid water turns to water vapor. This is an example of
A physical change
B chemical change
C chemical equation
D chemical formula
ANSWER: A

26. STANDARD 5e
Students know how to determine whether a solution is acidic, basic, or neutral

27. ACIDS AND BASES Properties of acids: Taste sour Corrosive
Conduct electricity
pH range of
Changes blue litmus paper to red

28. ACIDS AND BASES Properties of bases: Tastes bitter Feels slippery
Conducts electricity
Corrosive
pH range of 7.1 – 14.0
Changes red litmus paper to blue

29. ACIDS AND BASES
If the pH of a solution is 7.0 then the solution is considered neutral
Water has a pH of 7.0

30. ACIDS AND BASES
71. Which of the following things could be used to determine whether a substance is an acid or a base?
A an indicator
B litmus paper
C pH meter
D all of the above
ANSWER: D

31. ACIDS AND BASES 72. These data indicate that gastric juice is a
A strong acid
B strong base
C weak acid
D weak base
ANSWER: A

32. ACIDS AND BASES A an acid B a base C an indicator D a solvent
73. A substance that turns red litmus paper blue is
A an acid
B a base
C an indicator
D a solvent
ANSWER: B

33. STANDARD 6a
Students know that carbon, because of its ability to combine in many ways with itself and other elements, has a central role in the chemistry of living organisms

34. CHEMISTRY OF LIVING THINGS
CARBON - has four valence (outer) electrons and so it can make four bonds
Carbon atoms bonded together with single, double, or triple bonds can form straight chains, branched chains, or rings
Carbon’s ability to form four bonds results in millions of different shaped carbon-based molecules that allow them to have many different functions in living organisms C

35. CHEMISTRY OF LIVING THINGS
74. Unlike the atoms of most other elements, carbon atoms have which number of bonding electrons?
A 1
B 2
C 3
D 4
ANSWER: D

36. CHEMISTRY OF LIVING THINGS
75. Carbon-based molecules have a wide range of chemical properties because they
A have covalent bonds
B have the same shape
C can form many different shapes
D always form straight chains
ANSWER: C

37. STANDARD 6b
Students know that living organisms are made of molecules consisting largely of carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur

38. CHEMISTRY OF LIVING THINGS
An organic compound contains carbon
Organic compounds are found in all living organisms
Organic compounds include hydrocarbons, alcohols, organic acids, and polymers

39. carbon hydrogen nitrogen oxygen sulfur phosphorus
Other Important Atoms in Living Things
Most organic molecules in living things contain
carbon
hydrogen
nitrogen
oxygen
sulfur
phosphorus
NCHOPS

40. Chemistry of Living Things
76. Compounds that contain the element carbon are called
A organic compounds
B polar molecules
C nonpolar molecules
D hydrocarbons
ANSWER: A

41. Chemistry of Living Things
77. Which chemical formula does not represent an organic compound?
A CH3OH
B NH3
C C6H14
D CHCl3
ANSWER: B

42. Chemistry of Living Things
78. Which of the following elements is not an important component of organisms?
A nitrogen
B oxygen
C phosphorus
D potassium
ANSWER: D

43. STANDARD 6c
Students know that living organisms have many different kinds of molecules, including small ones, such as water and salt, and very large ones, such as carbohydrates, fats, proteins, and DNA

44. Chemistry of Living Things
Carbohydrates are polymers made of smaller molecules called glucose. Includes sugars, starch, and cellulose. Provides energy for living organisms
Proteins are polymers made up of smaller molecules called amino acids. Proteins are used to build and repair body parts
Lipids are polymers made from three fatty acids and alcohol named glycerol. Lipids include fats, oils, and waxes and are used to store energy for living organisms
Nucleic acids are very large polymers made from four smaller molecules called nucleotides. Two types: DNA and RNA. Carries genetic information

45. Chemistry of Living Things
Smaller molecules that living organisms need to survive include water, vitamins, minerals, and salts
Most chemical reactions that occur in living things take place in water
Vitamins and minerals serve as helper molecules in many life processes
Salts are required for many functions, such as contracting muscle, transmitting nerve impulses, and balancing blood pH

46. Chemistry of Living Things
79. Which of the following is the smallest molecule?
A protein
B sugar
C salt
D carbohydrate
ANSWER: C

47. Chemistry of Living Things
80. Which molecule is NOT a chemical used by living organisms?
A lipid
B nucleic acid
C carboxylic acid
D protein
ANSWER: C

48. Chemistry of Living Things
82. Which of the following kinds of chemical compounds does not contain carbon?
A sugar
B lipid
C water
D protein
ANSWER: C