How much heat in kilocalories is absorbed when 22.0 g of 2-propanol, rubbing alcohol, evaporates after being rubbed on the skin? The heat of vaporization of 2-propanol is 159 cal/g.

Question

How much heat in kilocalories is absorbed when 22.0 g of 2-propanol, rubbing alcohol, evaporates after being rubbed on the skin? The heat of vaporization of 2-propanol is 159 cal/g.
Analysis
Use the heat of vaporization to convert grams to an energy unit, calories. Calories must also be
converted to kilocalories using a cal–kcal conversion factor.

Accepted Answer

[1] Identify the original quantity and the desired quantity.

22.0 g ? kilocalories
original quantity desired quantity

[2] Write out the conversion factors.
• We have no conversion factor that directly relates grams and kilocalories. We do know, however,how to relate grams to calories using the heat of vaporization, and calories to kilocalories.

[3] Solve the problem.

Question 4.sp.6: How much heat in kilocalories is absorbed when 22.0 g of 2-p...

Related Answered Questions