Students practice identifying key laboratory safety hazards by drawing lines to match standard warning symbols with their correct definitions.

To solve this matching task, we need to look at each hazard symbol and pair it with the correct description of the danger it represents.

1. Explosive Symbol (First symbol - exploding bomb): This symbol shows an object bursting apart. It matches the description for Explosive, which says "The substance reacts violently when heated or struck."
2. Flammable Symbol (Second symbol - flame): This is a picture of a fire. It matches Flammable, meaning "The substance catches fire easily."
3. Irritant Symbol (Third symbol - cross): This is a large 'X'. In hazard signs, this usually means the substance is an Irritant. The description says "The substance produces vapours or fumes that irritate the eyes, nose and throat."
4. Radioactive Symbol (Fourth symbol - trefoil): This symbol (three blades around a circle) is the universal sign for radiation. It matches Radioactive, which states "The substance emits harmful radiation."
5. Toxic Symbol (Fifth symbol - skull and crossbones): This is the classic "poison" symbol. It matches Toxic, meaning "The substance is harmful in small doses."
6. Corrosive Symbol (Sixth symbol - liquid pouring on hand/surface): This image shows liquid dripping from a test tube onto a surface and a hand, causing damage. This matches Corrosive, which says "The substance corrodes (eats away) other substances."
7. Biohazard Symbol (Seventh symbol - circles and curves): This unique symbol is used for biological dangers. It matches Biohazardous, described as "A poisonous substance of biological nature."

Final Answer:
1. Explosive (Exploding bomb symbol)
2. Flammable (Flame symbol)
3. Irritant (Cross symbol)
4. Radioactive (Trefoil symbol)
5. Toxic (Skull and crossbones symbol)
6. Corrosive (Liquid pouring on hand symbol)
7. Biohazardous (Biohazard symbol)