Molecules and Compounds

What You'll Learn

Molecules form when two or more atoms bond together. A water molecule has two hydrogen atoms bonded to one oxygen atom, written as H₂O.

Key Words

condensation
boiling
density

Materials Needed

salt
sugar
vinegar

Safety First

Use materials only as directed in the experiment.
Keep small objects away from young children.
Work in a well-ventilated area when using vinegar or other strong-smelling substances.

Steps

Step 1 — Read

Review the background information on Properties of Matter before starting.

Step 2 — Do

Mix baking soda and vinegar in a sealed bag. Weigh the bag before and after. Did the mass change? Explain why or why not using the law of conservation of mass.

Step 3 — Observe

Note any unexpected results and think about why they happened.

Step 4 — Record

Share your findings with the class or a partner and discuss what you learned.

Check Your Understanding

Question 1

1 of 3

What is the smallest unit of an element?