CAN I PLEASE GET SOME HELP? You accidentally spilled an unknown liquid on a lab bench. It spreads out across the lab bench and quickly evaporates. What can you infer about the structure of the molecules? Explain your reasoning.

Which of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.