Worksheet: Elements, Atoms, and Molecules

In this worksheet, we will practice defining elements, atoms, and molecules and using these terms in the context of materials and physical processes.


What is the difference between a sulfur atom and a sulfur molecule?

  • ASulfur atoms consist of multiple sulfur molecules bonded together.
  • BSulfur atoms are reactive while sulfur molecules are not.
  • CSulfur atoms can be divided into smaller units, while sulfur molecules cannot.
  • DA sulfur molecule consists of multiple sulfur atoms bonded together.


Which of the following best describes a molecule?

  • AAtoms of two or more elements bonded together
  • BA mixture of different elements
  • CA single atom of an element
  • DAtoms chemically bonded together in a discrete unit


Which of the following best describes an element?

  • AA pure substance
  • BAny of the fragments that make up a molecule
  • CA substance made from more than one type of atom
  • DThe name shared by atoms containing the same number of protons


Which one of the following is true of an element?

  • AYou can divide up an element into infinitely many pieces.
  • BElements are made of at least two types of atom, bonded together.
  • CElements in the Periodic Table are arranged in order of increasing mass.
  • DAll the atoms of an element have the same number of protons in their nuclei.
  • EAll elements are found in nature in their pure states.


Which of the following is not an element?

  • ACarbon
  • BIron
  • CMolybdenum
  • DSteel
  • EUranium


Which of the following is true for molecules?

  • AMolecules have crystalline structures.
  • BAll molecules are composed of more than one type of atom.
  • CAll molecules are made of multiple atoms, all of the same type.
  • DMolecules are distinct, covalently-bonded collections of atoms.
  • EOnce you make a molecule out of atoms, you cannot get the constituent atoms back.


What is the symbol for an atom of the element chlorine?

  • A C l 2
  • B C l
  • C C l 2
  • D C l
  • E C l +


What is the symbol for molecular oxygen?

  • A O 3
  • B O
  • C 2 O
  • D O 2
  • E O 3

Nagwa uses cookies to ensure you get the best experience on our website. Learn more about our Privacy Policy.