2.1 Matter l

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

• Molecule

• Atom

• Element

According to Dalton's atomic theory, what happens to atoms during a chemical reaction?

• They are rearranged

• They are destroyed

• They are created

Which of the following statements about isotopes is true?

• Isotopes have the same number of neutrons

• Isotopes have different atomic numbers

• Isotopes have the same number of protons

What is the primary factor that determines the mass of an atom?

• Number of electrons

• Number of protons and neutrons

• Size of the electron cloud

Which of the following best describes a covalent bond?

• Attraction between ions

• Sharing of electrons

• Transfer of electrons

What is the maximum number of electrons that can occupy the second shell of an atom?

• 18

• 8

• 2

Which of the following elements is a noble gas?

• Hydrogen

• Helium

• Oxygen

What is the pH of a neutral solution?

• 0

• 7

• 14

What is the primary reason metals are good conductors of electricity?

• They have free-moving electrons

• They have high melting points

• They are ductile

What is the term for the process of a solid turning directly into a gas?

• Deposition

• Sublimation

• Evaporation