I) Add dilute hydrochloric acid to sodium carbonate in a conical flask.

a)

i) Add dilute hydrochloric acid to sodium carbonate in a conical flask.

ii) Pass the gas produced through a delivery tube into a test tube containing lime water.

iii) Bubble the gas through lime water (calcium hydroxide solution).

iv) Observe the change in the lime water.

b)

• Effervescence (fizzing) is observed in step I.
• The lime water turns milky (cloudy) in step IV.

c) The gas produced is carbon dioxide.

a)
A: Irritant / Harmful / Warning
B: Corrosive
C: Flammable
D: Toxic / Poisonous
E: Explosive

b)
A (Irritant/Harmful): Ethanol, Ammonia solution
B (Corrosive): Concentrated hydrochloric acid, Sodium hydroxide
C (Flammable): Petrol, Propanone (Acetone)
D (Toxic/Poisonous): Potassium cyanide, Mercury compounds
E (Explosive): Nitroglycerin, TNT (Trinitrotoluene)

c)

• Keep the chemical away from open flames, sparks, and other ignition sources.
• Ensure the area is well-ventilated or use a fume hood.