Answer:
Explanation:
Since 100C is the boiling temperature for water, for this problem we don't need to calculate the energy needed to get to the boiling point, just the heat or energy needed to vaporize the water to steam at 100C.
The formula for this is q=m(delta)
q is Joules of heat needed to vaporize the water to steam at 100C
m is mass in grams
Delta is in Joules per gram and can be looked up for water at this temperature. Here, it is approximately 2260J/g. This online lecture should help ease understanding: https://cabrillo.instructure.com/courses/10267/modules/items/256219
Therefore...
q=2.5g (2260J/g)= 5650J = 5.65kJ
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