Question

if a piece of glass tubing gets stuck in a rubber stopper, the safest procedure is to

a. put the tubing through a hole in a lab table and push hard.
b. discard both stopper and the tube.
c. heat the stopper over the flame.
d. twist and pull on the stopper and the tube as hard as you can.

Explanation:

Analyze the safety risks of stuck glass tubing

Glass tubing stuck in a rubber stopper is a common laboratory hazard. Forcing the glass by pushing, pulling, or twisting hard can cause the glass to snap, leading to severe puncture wounds or cuts. Therefore, any procedure involving excessive force (such as options A and D) is highly dangerous.

Evaluate thermal methods

Heating a rubber stopper over an open flame (option C) is unsafe. Rubber is flammable, can melt, and releases toxic fumes when heated directly. Additionally, heating does not guarantee safe release and introduces burn hazards.

Determine the safest procedure

When glass tubing is firmly stuck in a rubber stopper and cannot be easily removed using standard safe techniques (such as using a lubricant like glycerin or a specialized cork borer to slide over the tubing), the safest course of action to prevent injury is to discard both the stopper and the tube (option B). This eliminates the risk of glass breakage and physical harm.

Answer:

• A. put the tubing through a hole in a lab table and push hard.
• B. discard both stopper and the tube. (Correct answer)
• C. heat the stopper over the flame.
• D. twist and pull on the stopper and the tube as hard as you can.