Liquids stored under pressure ________ their normal boiling point temperature cause increased hazards because of flashing.

• A. Below
• B. Above
• C. At
• D. Between

Answer: (B)

The key idea is that boiling point depends on pressure. The normal boiling point is defined at standard atmospheric pressure. When a liquid is stored under pressure, its boiling point increases above that normal value, so the liquid can remain a liquid even at temperatures higher than its normal boiling point. If the pressure is then released, the liquid suddenly experiences a lower pressure, and it can rapidly boil into vapor—this rapid vaporization is flashing. That flashing creates hazards such as violent vapor expansion, splashing, and heat transfer risks. So storing liquids under pressure means they can be hotter than their normal boiling point without boiling, but releasing the pressure can cause flashing, which is why the hazard increases.