Oxygen

• FORMULA: O2 -> diatomic gas
• PHYSICAL PROPERTIES:

  1. colourless
  2. odourless gas
  3. welding e.g oxy-acetylene welding [+ mixed with oxygen to increase the temperature at which it burns out]
  4. Slightly soluble in water
  5. Neutral
• Preparation of oxygen:

  Hydrogen peroxide will decompose to form oxygen and water

  Manganese(IV) oxide acts as a catalyst (+ definition of catalyst)

  Oxygen collected over water as it is not very soluble in water (Heard through bubbles in trough)

  OBSERVATIONS:

  Bubbles of gas are given of, black solid remains at the bottoms of the flask, heat is given off
• Draw the diagram for laboratory Preparation of Oxygen

  Diagram:

  
• TEST FOR OXYGEN:

  1. Apply a glowing splint
  2. Oxygen relights a glowing splint
• USES OF OXYGEN:

  1. Breathing apparatus
  2. welding
• CARBON REACTING WITH OXYGEN:

  OBSERVATION: Black carbon burns with an orange, soot flame forming a colourless gas

  PRODUCT: Carbon dioxide

  NATURE OF OXIDE: Acidic

  EQUATION: C + O2 -> CO2
• SULFUR REACTING WITH OXYGEN:

  OBSERVATION: Yellow solid sulfur melts to a red liquid and burns with a blue flame giving a colourless, pungent gas

  PRODUCT: Sulfur dioxide

  NATURE OF OXIDE: Acidic

  EQUATION: S + O2 -> SO2
• MAGNESIUM REACTING WITH OXYGEN:

  OBSERVATION:Grey,solid magnesium burns with s. bright white light, releasing heat and producing a white solid

  PRODUCT: magnesium oxide

  NATURE OF OXIDE: Basic

  EQUATION: 2Mg + O2 -> 2MgO
• IRON REACTING WITH OXYGEN:

  OBSERVATION: Grey, solid iron filings burn with orange sparks producing a black solid

  PRODUCT: Iron Oxide

  NATURE OF OXIDE: Basic

  EQUATION: Fe + 3O2 -> 2Fe2O
• COPPER REACTING WITH OXYGEN:

  OBSERVATION: Red-Brown solid glows red and a black solid is formed

  PRODUCT: copper oxide

  NATURE OF OXIDE: basic

  EQUATION: 2Cu +O2 -> 2CuO
• METAL OXIDE = BASIC

  NON- METAL OXIDE = ACIDIC