Identify the symbols for chemical hazards, list chemicals associated with them, and state safety precautions for flammable substances.

3a) Write out the procedure used by the student in each of the steps:

• I. Sodium carbonate is reacted with dilute hydrochloric acid in a flask.
• II. The gas produced from the reaction is passed through a delivery tube.
• III. The gas is then bubbled through lime water (calcium hydroxide solution) in a test tube.
• IV. The lime water is observed to turn milky.

3b) Give two (2) observations made in the test:

• Gas bubbles are produced when sodium carbonate reacts with dilute hydrochloric acid.
• The lime water turns milky.

3c) Write the conclusion drawn from the test:

• The gas produced is carbon dioxide, as it turned lime water milky.

4a) Identify each of the symbols labelled A, B, C, D and E:

• A. Irritant or Harmful
• B. Corrosive
• C. Flammable
• D. Toxic or Poisonous
• E. Explosive

4b) Name two (2) chemicals which can be associated with each symbol A, B, C, D and E:

• A. Ethanol, Ammonia
• B. Concentrated hydrochloric acid, Sodium hydroxide
• C. Acetone, Petrol
• D. Cyanide, Mercury compounds
• E. Nitroglycerin, Ammonium nitrate

4c) State two (2) safety precautions that should be taken when handling chemicals with symbol C:

• Keep the chemical away from open flames or other ignition sources.
• Ensure the area is well-ventilated to prevent the accumulation of flammable vapors.