Chemistry Clarity · chemistryclarity.com

Classification of Matter: Flashcards

Revise elements, compounds and mixtures, physical and chemical changes, and separation methods.

11 cardsBeginner

11 cards

  1. Question
    What is matter?
    Answer

    Anything that has mass and takes up space.

  2. Question
    What is an element?
    Answer

    A pure substance made of only one kind of atom. It cannot be broken down by chemical reactions.

  3. Question
    What is a compound?
    Answer

    A pure substance of two or more elements chemically bonded in a fixed ratio, e.g. HX2O\ce{H2O}.

  4. Question
    What is a mixture?
    Answer

    Two or more substances physically mixed, not chemically bonded. Its composition can vary.

  5. Question
    Homogeneous or heterogeneous: salt water?
    Answer

    Homogeneous (a solution): it is uniform throughout.

  6. Question
    Is OX2\ce{O2} an element or a compound?
    Answer

    An element: its molecules contain only one kind of atom.

  7. Question
    Physical or chemical change: iron rusting?
    Answer

    Chemical: a new substance (iron oxide) forms.

  8. Question
    Physical or chemical change: ice melting?
    Answer

    Physical: it is still water (HX2O\ce{H2O}).

  9. Question
    Which method separates sand from water?
    Answer

    Filtration.

  10. Question
    Which method gets pure water from sea water?
    Answer

    Distillation: boil the water and condense the vapour.

  11. Question
    Give an example of "dissolving" that is a chemical change.
    Answer

    Calcium oxide in water: CaO+HX2O→Ca(OH)X2\ce{CaO + H2O -> Ca(OH)2}. Evaporation gives calcium hydroxide, not calcium oxide.