Final answer:
The principal hazard of an old bottle of picric acid with residue on the cap is that it may be highly explosive. Do not open the bottle; notify a professional to safely dispose of it, as per chemical safety guidelines.
Step-by-step explanation:
Handling Picric Acid with Residue on the Cap
The principal hazard when you find an old bottle of picric acid with residue on the cap is that it can become highly explosive when dry. Picric acid is a strong acid that can also cause severe burns if it comes into contact with the skin. Due to its sensitivity, you should handle such a situation with extreme caution. First, do not attempt to open the bottle, as disturbing the crystals may trigger an explosion. Immediately notify your teacher or a professional who deals with hazardous materials. They can assess the situation and take the necessary steps to safely neutralize and dispose of the compound according to proper protocols.
Review the safety precautions for chemical handling, including wearing appropriate protective equipment, and ensure that you are trained and informed about the specific dangers of substances like picric acid. Disposal should never be attempted by unqualified individuals and should not involve pouring chemicals down the sink or in regular trash. The proper procedure often involves contacting waste disposal experts who handle hazardous waste.
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