Fall 2025 Semester Review

Which of these should you NEVER do in a lab?

• Wear close-toed shoes in the lab.

• Tie long hair back

• Wear goggles to protect your eyes

• Never eat or drink in a lab.

When should we use the safety shower?

• When you haven't showered after practice

• When you are sweaty

• Use the safety shower immediately after exposure to hazardous substances.
• Use the safety shower for routine cleaning.

What is the purpose of the fume hood?

• To provide a workspace for experiments.
• To store chemicals safely.
• The purpose of the fume hood is to protect users from hazardous fumes and vapors.
• To enhance the aesthetic of the laboratory.

What is the difference between chemical and physical change?

• Chemical changes only occur at high temperatures; physical changes occur at any temperature.
• Chemical changes create new substances; physical changes do not.
• Physical changes involve the creation of new substances; chemical changes do not.
• Chemical changes are always reversible; physical changes are not.

Choose an example of a physical change

• Melting ice into water
• Burning wood to ash
• Silver Tarnishing

• Fireworks exploding

Give an example of a chemical change

• Dissolving sugar in water
• Melting of ice
• Rusting of iron
• Boiling water

Who discovered the atom?

• Albert Einstein
• John Dalton
• Niels Bohr
• Erwin Schrödinger

What did the scientist JJ Thompson discover?

• The electron.
• The nucleus.
• The neutron.
• The proton.

What does the modern atomic theory state?

• Atoms can be created and destroyed in chemical reactions.
• All matter is continuous and not made of atoms.
• Atoms are the largest thing in the world

• The modern atomic theory states that matter is made up of indivisible atoms, which combine in fixed ratios to form compounds.

What subatomic particles are located in the nucleus?

• Protons and neutrons
• Electrons and positrons
• Photons and neutrinos
• Quarks and leptons