Practice Quiz

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

• Atom
• Molecule
• Compound
• Ion

Which scientist proposed the idea that atoms are solid, indivisible particles?

• Rutherford
• Thomson
• Dalton
• Bohr

Which atomic model introduced the concept of electrons orbiting a nucleus?

• Dalton's model
• Thomson's model
• Bohr's model
• Rutherford's model

According to kinetic molecular theory, what increases as a substance is heated?

• Mass
• Volume
• Particle speed
• Number of atoms

What tool organizes elements by increasing atomic number and recurring chemical properties?

• Element chart
• Periodic Table
• Atomic diagram
• Chemical index

Which type of chemical bond involves the sharing of electrons between atoms?

• Ionic bond
• Metallic bond
• Hydrogen bond
• Covalent bond

What property is defined as mass per unit volume?

• Weight
• Molarity
• Volume
• Density

What does a balanced chemical equation demonstrate?

• Change in energy
• Change in state
• Conservation of matter
• Change in volume

What is the key factor that distinguishes a chemical change from a physical change?

• Change in shape
• Change in state
• Formation of new substances
• Change in size

Which element, the simplest of all, has the atomic number 1?

• Helium
• Lithium
• Hydrogen
• Carbon