Question

How much energy is required to completely vaporize 250 grams of liquid water that is already at 100 degrees Celsius? Show your work & units. Expected Answer = 565,000 J

Answer 1

564100J (~ 565000J) of heat energy is required.

Step-by-step explanation:

The enthalpy of vaporization of water is 2256.4J/g, meaning that 2256.4J of heat is required to convert 1 gram of water at 100 degrees Celcius to steam at 100 degrees Celcius.

In your case, we have 250g of water at 100C and we want to vaporize it to steam (also at 100C).

This requires ΔH = 2256.4(250) = 564100J of heat energy.