New
New

    Atoms, elements and compounds

    I can describe elements as being made up of only one type of atom, and that elements can combine chemically to form compounds.

    New
    New

      Atoms, elements and compounds

      I can describe elements as being made up of only one type of atom, and that elements can combine chemically to form compounds.

      Lesson details

      Key learning points

      1. Atoms of every element consist of the same three subatomic particles.
      2. All elements consist of their own atoms, with a unique number of protons defining the element.
      3. Everything around us is made of different combinations of atoms, either on their own, or in compound form.
      4. We use element symbols in formulae as a common language to share chemical compositions.

      Keywords

      • Atom - An atom is the smallest particle that everything is made up of.

      • Element - An element is made up of only one type of atom, a list of elements can be found on the periodic table.

      • Compound - A compound is made of two or more different elements chemically bonded together.

      • Chemical formula - The chemical formula of a molecule is a shorthand way of listing the type and number of atoms in a compound.

      • Chemical composition - The chemical composition tells you the different types of atoms in a chemical.

      Common misconception

      Students often think that an elemental diatomic molecule, e.g. hydrogen, is a compound because they see two atoms chemically joined together.

      The teacher needs to emphasise the definition for compounds. Molecules are not the same as compounds, some molecules are compounds, not all.

      Use molecular models to make up molecules of elements and compounds and practice writing formulae from these models.
      Teacher tip

      Licence

      This content is © Oak National Academy Limited (2026), licensed on Open Government Licence version 3.0 except where otherwise stated. See Oak's terms & conditions (Collection 2).

      Lesson video

      Loading...

      Prior knowledge starter quiz

      Download quiz pdf

      6 Questions

      Q1.
      What is matter?

      Correct answer: anything that takes up space and has mass
      only liquids and solids
      only gases
      energy

      Q2.
      Match the following elements with their correct atomic number (found on the periodic table).

      Correct Answer:Neon,10

      10

      Correct Answer:Iron,26

      26

      Correct Answer:Chlorine,17

      17

      Correct Answer:Sodium,11

      11

      Q3.
      Melting ice is an example of ...

      a chemical change.
      Correct answer: a physical change.
      both a physical and chemical change.
      neither a physical nor chemical change.

      Q4.
      Match the subatomic particles with their correct charge.

      Correct Answer:Proton,Positive

      Positive

      Correct Answer:Neutron,Neutral

      Neutral

      Correct Answer:Electron, Negative

      Negative

      Q5.
      Where is the majority of an atom's mass located?

      in the electrons
      Correct answer: in the nucleus
      evenly distributed throughout the atom

      Q6.
      The term "nucleus" is used in multiple subjects but refers to different things. What does the nucleus refer to in chemistry?

      Correct answer: the centre of an atom, containing protons and neutrons
      the part of a cell that contains genetic material
      a cluster of neuronal cell bodies within the brain
      a dense cluster of stars or galaxies, especially at the centre of a galaxy

      Assessment exit quiz

      Download quiz pdf

      6 Questions

      Q1.
      Which subatomic particles are the basic building blocks of atoms?

      electrons only
      protons only
      protons and neutrons
      Correct answer: protons, neutrons and electrons
      none of these

      Q2.
      What defines an element?

      the number of electrons
      Correct answer: the number of protons
      the number of neutrons
      the number of molecules

      Q3.
      How do chemists communicate chemical compositions universally?

      through detailed descriptions
      Correct answer: by using element symbols in formulae
      with full chemical names

      Q4.
      Match the following terms with their definitions.

      Correct Answer:Atom,The smallest particle that everything is made up of.

      The smallest particle that everything is made up of.

      Correct Answer:Element,Made up of only one type of atom.

      Made up of only one type of atom.

      Correct Answer:Compound,Made of two or more different elements chemically bonded together.

      Made of two or more different elements chemically bonded together.

      Correct Answer:Chemical formula,A shorthand way of listing the type and number of atoms in a compound.

      A shorthand way of listing the type and number of atoms in a compound.

      Q5.
      Hydrogen (Hâ‚‚) is able to be described as ...

      a compound.
      Correct answer: an element.
      a mixture.
      Correct answer: a molecule.

      Q6.
      Everything around us is made of different combinations of , either on their own as elements, or in compound form.

      Correct Answer: atoms

      Lesson appears in

      UnitChemistry / Atomic structure and the periodic table

      UnitCombined science / Atomic structure and the periodic table