Strand IV
Use Scientific Knowledge from the Physical Sciences in Real-World Contexts


Science/Strand IV
Content Standard 2
All students will investigate, describe, and analyze ways in which matter changes; describe how living things and human technology change matter and transform energy; explain how visible changes in matter are related to atoms and molecules; and how changes in matter are related to changes in energy. (Changes in Matter)


Science/Strand IV/Content Standard 2
High School


Science/Strand IV/Content Standard 2/High School
Benchmark 4
Describe energy transformations involved in physical, chemical, and nuclear changes, and contrast their relative magnitudes.

Benchmark Clarification

Physical, chemical, and nuclear changes are accompanied by changes in energy. Energy exists in different forms: potential (energy due to position), kinetic potential (energy of motion), heat, light, electrical, chemical, sound

Energy can change its form at any time during everyday physical and chemical changes, but it can never be created or destroyed.

Only in nuclear changes are energy and matter not conserved. During these changes, some matter is converted into energy or energy into matter according to Einstein’s equation, E = mc2 (energy = mass times the square of the speed of light).

Because matter and energy can be converted from one to the other, the total amount of matter and energy in the universe remains constant and unchanged.

Students will

  • Compare the amount of energy associated with nuclear, chemical and physical changes
  • Recognize that nuclear changes involve the greatest amount of energy

Key Concept / Real World Context / Instructional Example / Assessment Example / Resources


Science/Strand IV/Content Standard 2/High School/Benchmark 4
Key Concept

  • potential energy
  • kinetic energy
  • heat
  • light
  • electrical energy
  • chemical energy
  • sound
  • temperature changes

Original sources of energy:

  • sun
  • radioactivity

Conservation of energy

Conservation of mass/energy: E = mc2

See Common energy transformation (SCI.IV.2.MS.4).
See Nuclear changes (SCI.IV.2.HS.3).


Science/Strand IV/Content Standard 2/High School/Benchmark 4
Real World Context

  • common physical changes
  • chemical changes
  • nuclear changes
  • changes of state
  • burning
  • electrical decomposition of water
  • photosynthesis
  • cellular respiration
  • fireworks and dynamite
  • nuclear power
  • stars


Science/Strand IV/Content Standard 2/High School/Benchmark 4
Instructional Example

Benchmark Question: How does matter change?

Focus Question: How does energy get transformed in a chemical change?

Working in small lab groups, students will observe photosynthesis in green plants by performing the following steps:

1. Place a sprig of a submerged aquatic plant (e.g., Elodea anacharis) in a small test tube.

2. Fill the test tube with water and place inverted into a beaker filled with water. The test tube should still be completely filled with water.

3. Repeat steps one and two for a second test tube.

4. Shine a bright light source on one set-up (e.g., lamp, sunlight) and place the other in a dark location. Let both stand for at least half an hour.

Observe the plants in both test tubes. Small bubbles of oxygen (from photosynthesis in the plant) should be filling the top of the test tube under the bright light, while the one in the dark has few or no bubbles. Students will analyze the results of the experiment and discuss the source of energy required to produce the gas. Using references, each student will diagram the energy transformation in photosynthesis. Each student will write an explanation of the energy transformation in photosynthesis, including the fact that light energy is absorbed and used by photosynthesis to produce the bubbles of oxygen.

Constructing: (SCI.I.1.HS.4), (SCI.I.1.HS.5).

Reflecting: (SCI.II.1HS.3), (SCI.II.1.HS.6).


Science/Strand IV/Content Standard 2/High School/Benchmark 4
Assessment Example

Students will create a storyboard illustrating the energy transformation and the chemical reactions of photosynthesis. They will begin with sunlight and end with stored energy in the new chemical bonds of products.

(Give students rubric before activity.)

Scoring Rubric






Completeness of storyboard illustration

Illustrates incompletely and/or out of sequence.

Illustrates general sequence correctly but lacks detail.

Illustrates complete chemical reaction and energy transformation.

Creates and illustrates complete in-depth storyboard.

Accuracy of explanation

Explains inaccurately and with no details.

Explains accurately but with few details.

Explains accurately and completely with some details.

Explains accurately and completely with many details.


Science/Strand IV/Content Standard 2/High School/Benchmark 4