Using the "1300 rule", what is the concentration of vapor in the headspace of a drum of acetone with a vapor pressure of 180 mmHg?

The "1300 rule" is a guideline used to estimate the concentration of a vapor in the headspace of a container based on the vapor pressure of the liquid and the ambient temperature. The rule suggests that for every 1 mmHg of vapor pressure at 20°C, the corresponding concentration of vapor can be approximated at 1,300 ppm.

In this scenario, acetone has a vapor pressure of 180 mmHg. To find the concentration in ppm, you multiply the vapor pressure by 1,300:

180 mmHg * 1,300 ppm/mmHg = 234,000 ppm.

This calculation shows that the concentration of vapor in the drum's headspace is indeed 234,000 ppm, making it the correct answer. The "1300 rule" effectively allows for a straightforward conversion, which is particularly useful when assessing potential hazards associated with flammable vapors like acetone.