Chapter 9 Vocabulary Practice

What is the smallest piece of an element that still represents the element?

• Molecule

• Atom

• Compound

• Ion

Which atomic particle has a positive charge?

• Electron

• Neutron

• Proton

• Ion

What is the term for the number of protons in an atom of an element?

• Mass number

• Atomic number

• Isotope

• Ion

Which of the following describes an atom that is no longer neutral because it has gained or lost electrons?

• Isotope

• Ion

• Neutron

• Proton

Calculate the mass number of an atom with 6 protons and 8 neutrons.

• 6

• 8

• 14

• 12

What is the average atomic mass of an element?

• The sum of protons and neutrons in an atom

• The number of protons in an atom

• The average mass of an element’s isotopes, weighted according to the abundance of each isotope

• The mass of the most common isotope

Describe what happens during nuclear decay.

• An atom gains electrons.

• An unstable atomic nucleus changes into another more stable nucleus by emitting radiation.

• An atom loses protons.

• An atom becomes an ion.

Which term describes elements that spontaneously emit radiation?

• Radioactive

• Isotopic

• Ionic

• Neutral

In which area of an atom is an electron most likely to be found?

• Nucleus

• Proton cloud

• Electron cloud

• Neutron cloud

What is the charge of a neutron?

• Variable

• Negative

• Neutral

• Positive