Chemistry Quiz

What is the smallest particle of an element that retains its chemical properties?

• Molecule

• Atom

• Electron

• Proton

Which of the following is a compound?

• Oxygen (O₂)

• Hydrogen (H₂)

• Water (H₂O)

• Nitrogen (N₂)

Which subatomic particle has a negative charge?

• Proton

• Neutron

• Electron

• Nucleus

Isotopes of an element have:

• Same number of protons, different number of neutrons

• Same number of neutrons, different number of protons

• Different numbers of protons and electrons

• Same mass numbers

Which element has the atomic number 6?

• Oxygen

• Nitrogen

• Carbon

• Helium

What type of reaction is: 2H₂ + O₂ → 2H₂O?

• Decomposition

• Single replacement

• Combination

• Double replacement

Which law states that mass is neither created nor destroyed in a chemical reaction?

• Law of Definite Proportions

• Law of Conservation of Mass

• Law of Multiple Proportions

• Avogadro's Law

A catalyst:

• Increases the activation energy

• Is consumed in the reaction

• Speeds up the reaction without being consumed

• Slows down the reaction

In a redox reaction, oxidation refers to:

• Gain of electrons

• Loss of electrons

• Gain of protons

• Loss of neutrons

Which of the following is an exothermic process?

• Melting ice

• Boiling water

• Combustion of gasoline

• Photosynthesis