Flash Point is defined as which of the following?

Flash Point is defined as which of the following?

• A. minimum temperature at which a liquid gives off vapor within a test vessel in sufficient quantity to form an ignitable mixture
• B. the temperature at which a liquid boils
• C. the density of the liquid
• D. the ignition temperature of a vapor

Answer: (A)

Flash point is the lowest temperature at which a liquid can give off enough vapor to form an ignitable mixture with air in the test vessel. This marks the point where handling conditions start to present a fire hazard, since vapors above this level can ignite if an ignition source is present. The other ideas describe different properties: boiling point is the temperature at which a liquid boils and becomes vapor, not the threshold for forming a flammable vapor-air mixture; density has nothing to do with flammability; and the ignition temperature of a vapor refers to how hot the vapor would need to be to ignite once ignited, not the point at which vapors begin to form an ignitable mixture.

Flash point is the lowest temperature at which a liquid can give off enough vapor to form an ignitable mixture with air in the test vessel. This marks the point where handling conditions start to present a fire hazard, since vapors above this level can ignite if an ignition source is present. The other ideas describe different properties: boiling point is the temperature at which a liquid boils and becomes vapor, not the threshold for forming a flammable vapor-air mixture; density has nothing to do with flammability; and the ignition temperature of a vapor refers to how hot the vapor would need to be to ignite once ignited, not the point at which vapors begin to form an ignitable mixture.