Classifying Matter, Properties and Changes

Which of these is a pure substance?

A drop of melted wax falls on a table. It cools and becomes solid. How has it changed?

Suppose that you examine an unknown liquid. You determine that it contains a single type of molecule. What is the liquid?

An example of evaporation is when:

Which of these is a physical change, not a chemical change?

As your stomach digests food, this would be considered a:

Which of the following choices contains only physical properties?

As a solid heats up, its particles gain energy and vibrate faster. When they vibrate enough, the particles move away from one another. This describes

Which of these has the highest melting point?

A red liquid and a yellow liquid are mixed together. The result is an orange liquid that bubbles. This is evidence of

A red and yellow liquid are mixed together. The result is an orange liquid. This is evidence of a

Which of these is a chemical change, not a physical change?

During the phase change lab, the H2O molecules were