Question
What is the density of water vapor in g/m3\textrm{g/m}^3 on a hot dry day in the desert when the temperature is 40.0C40.0^\circ\textrm{C} and the relative humidity is 6.00%?
Question by OpenStax is licensed under CC BY 4.0
Final Answer

3.07 g/m33.07\textrm{ g/m}^3

Solution video

OpenStax College Physics for AP® Courses, Chapter 13, Problem 56 (Problems & Exercises)

OpenStax College Physics, Chapter 13, Problem 56 (PE) video thumbnail

In order to watch this solution you need to have a subscription.

Start free trial Log in
vote with a rating of votes with an average rating of .

Calculator Screenshots

  • OpenStax College Physics, Chapter 13, Problem 56 (PE) calculator screenshot 1
Video Transcript
This is College Physics Answers with Shaun Dychko. We’re going to find the density of water vapor in the air when the temperature is 40 point zero degrees Celsius and the relative humidity is 6%. So relative humidity is the vapor density divided by the maximum possible vapor density at that temperature before it starts to rain if it goes beyond this saturation vapor density times 100%. So we'll solve for this by dividing both sides by 100 and then multiplying both sides by the saturation vapor density and then we get vapor density as relative humidity divided by 100 times saturation vapor density. So the saturation vapor density is something we need to look up in table 13.5. And so we follow the column of temperature down to 40 degrees Celsius and find that the saturation vapor density is 51.1 grams per cubic meter. So this is the maximum density of water vapor that's possible at this particular temperature and this works out to 3.07 grams per cubic meter.