Crystal Growth

Jane Pafundi

Growing Copper Sulfate Crystals

What is the effect of a seed crystal on crystal size on copper sulfate crystals

in a petri dish at room temperature?

Grade Eight

California Science Content Standards

Focus on Physical Science

Structure of Matter

1. Each of the more than 100 elements of matter has distinct properties and a distinct atomic structure. All forms of matter are composed of one or more of the elements. As a basis for understanding this concept:

c. Students know atoms and molecules form solids by building up repeating patterns, such as the

crystal structure of NaCl or long-chain polymers.

Reactions

1. Chemical reactions are processes in which atoms are rearranged into different combinations of molecules. As a basis for understanding this concept:

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

Investigation and Experimentation

1. Scientific progress is made by asking meaningful questions and conducting careful investigations. As a basis for understanding this concept and addressing the content in the other three strands, students should develop their own questions and perform investigations. Students will:

a. Plan and conduct a scientific investigation to test a hypothesis.

b. Evaluate the accuracy and reproducibility of data.

c. Distinguish between variable and controlled parameters in a test.

Variables Tested by students:

• • Food coloring

  • Distilled water

  • Temperature

  • Enclosed environment

  • Moist environment

Link to experiment set-up and results

http://docs.google.com/Doc?docid=0AVmciH52ITmPZGZxYnE3enJfMjJnd2N2ZHQ4eg&hl=en

Other Links

http://chemistry.about.com/od/crystalrecipes/a/coppersulfate.htm

http://video.about.com/chemistry/How-to-Make-Rock-Candy.htm