Reactions

Reactions to Oxygen:

Reaction Names:

  • Some metals react during burning (combustion).

  • It is either a oxidation or combustion reaction.

Metal Oxides:

  • Basic, alkaline in water.

  • Solid.

  • Metal + Oxygen —> Metal Oxide.

Examples:

  • Magnesium oxide:

    • Burns with a bright white light.

    • Forms white ash.

    • 2Mg + O2 —> 2MgO

  • Iron oxide:

    • Fe2O3 = Rust.

      • Reddish-brown.

      • Corrosion.

      • Occurs when oxygen reacts with iron in a moist area.

      • It’s slow.

      • Prevention: Galvanising (coat with zinc), electroplating (coat in chrome/tin), painting.

    • Fe3O4 = Magnetic Oxide.

      • Shiny, black substance.

      • Used in magnetic beads.

Non-Metal Oxides:

  • Can also combust.

  • Usually gasses.

  • Acidic.

  • Non-Metal + Oxygen —> Non-Metal Oxide.

Examples:

  • Carbon dioxide:

    • When it is burnt in the air, a colourless gas is formed.

    • To test for CO2 blow air into a vial of limewater.

    • C + O2 —> CO2

  • Sulfur dioxide:

    • Burns in oxygen with a bright blue flame, producing a colourless gas.

    • It is toxic with a gross smell.

    • S + O2 —> SO2

pH Neutralisation:

pH:

  • Scale of how acidic (0,1 - 6,9) or basic (7,1 - 14) a substance is.

  • Acids:

    • Sour.

    • Rough.

    • Reacts with metals to produce H2 gas.

    • Hydrochloric Acid (HCl), Sulfuric Acid (H2SO4), Nitric Acid (HNO3).

    • Citric Acid, Ethanoic Acid, Oxalic Acid, Carbonic Acid.

  • Bases:

    • Bitter.

    • Slippery.

    • Called alkaline when dissolved in water.

    • Sodium Hydroxide (NaOH), Potassium Hydroxide (KOH).

    • Ammonia (NH3), Baking Soda (NaHCO3), Magnesium Hydroxide.