Molecules and Compounds (Part 2)

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

compound
molecule
density

Materials Needed

paper towels
thermometer
strainer
ice cubes
salt
sugar

Safety First

Protect your work surface with newspaper or plastic.
Adult supervision recommended.
Do not taste any materials.

Steps

Step 1 — Read

Review the background information on Matter and Reactions 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?