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Chemistry 0620

2. Atoms, elements and compounds

Atomic structure, the Periodic Table, isotopes, and the three types of bonding.

  1. 2.1

    Elements, compounds and mixtures

    The difference between an element, a compound and a mixture.

    Full lesson2 questions4 cards
    • 2.1.1Describe the differences between elements, compounds and mixtures.
  2. 2.2

    Atomic structure and the Periodic Table

    Protons, neutrons and electrons, proton and nucleon number, electronic configuration, and its link to group and period.

    Full lesson2 questions5 cardsSimulationReview first: 2.1
    • 2.2.1State the relative charges and masses of protons, neutrons and electrons.
    • 2.2.2Define proton number and nucleon number and use them to determine the number of each particle.
    • 2.2.3Write the electronic configuration of the first 20 elements and relate it to group and period.
  3. 2.3

    Isotopes

    Atoms of the same element with different numbers of neutrons, and relative atomic mass.

    Full lesson2 questions3 cardsReview first: 2.2
    • 2.3.1Define isotopes and explain why they have identical chemical properties.
    • 2.3.2Calculate relative atomic mass from isotopic abundances.
  4. 2.4

    Ions and ionic bonds

    Formation of ions by electron transfer, ionic bonding, and the properties of ionic compounds.

    Full lesson1 questions4 cardsSimulationReview first: 2.2
    • 2.4.1Describe the formation of positive and negative ions by loss or gain of electrons.
    • 2.4.2Describe ionic bonding as the electrostatic attraction between oppositely charged ions in a giant lattice.
    • 2.4.3Explain the properties of ionic compounds in terms of their structure and bonding.
  5. 2.5

    Simple molecules and covalent bonds

    Sharing electron pairs, dot-and-cross diagrams, and the properties of simple molecular substances.

    Full lesson2 questions3 cardsSimulationReview first: 2.2
    • 2.5.1Describe the formation of a covalent bond as a shared pair of electrons between two non-metal atoms.
    • 2.5.2Draw dot-and-cross diagrams for simple molecules including H₂, Cl₂, H₂O, CH₄, NH₃, CO₂ and N₂.
    • 2.5.3Explain the low melting points and poor conductivity of simple molecular compounds in terms of weak intermolecular forces.
  6. 2.6

    Giant covalent structures

    Diamond, graphite and silicon(IV) oxide — structure, bonding and properties.

    Full lesson1 questions4 cardsReview first: 2.5
    • 2.6.1Describe the giant covalent structures of diamond and graphite and relate them to their properties and uses.
  7. 2.7

    Metallic bonding

    A lattice of positive ions in a sea of delocalised electrons, and why metals conduct and are malleable.

    Full lesson1 questions4 cardsReview first: 2.2
    • 2.7.1Describe metallic bonding as a lattice of positive ions in a sea of delocalised electrons.
    • 2.7.2Explain electrical conductivity and malleability in terms of metallic structure.