Model the process of igneous rock formation with this lab. Start by melting salol—an organic material that melts easily and crystallizes at room temperature. Students repeat the experiment using rapid cooling. This gives them two samples of crystalized substances to compare.
Students study grain size in the two samples they create before correlating their findings to rock samples in their classroom rock collection such as fine and coarse granite if available.
This experiment requires use of a small flame.
Use this to learn and reinforce answers to questions such as:
❑ How are igneous rocks formed?
❑ What explains the grain size of crystals in igneous rocks?
❑ Why are fossils not found in igneous rocks?
Concepts Addressed
♦ Minerals form from magma and lava
♦ There are three types of rocks (Sedimentary, Metamorphic, and Igneous)
♦ Igneous rocks form from crystallized lava or magma
Standards Addressed
NGSS MS-ESS2-1
TEKS 6.10B
VA SOL ES.5.a
Materials Needed: Salol (phenyl salicylate), small tea candles, lighter, metal spoons (dedicated to this experiment) craft sticks, ice, ceramic tile.
Teaching Time About 30–40 min.
Preparation Required
Collect old metal spoons and use them exclusively for this experiment. You can use them time after time. The salol can be reused. Order the salol from a scientific supply house.
Student Sheets Scaffolded writing prompts & lab reporting
Answer Keys and Teacher Notes address most questions and issues that might arise in this study—you shouldn’t have to do any outside research unless you want to.
