The question is incomplete, here is a complete question.
of is 289 J/g. What mass of this substance must evaporate in order to freeze 190 g of water initially at 17 degrees C? (heat of fusion of water is 334 J/g; specific heat of water is 4.18 J/g.K).
Answer : The mass of this substance evaporate to freeze must be, 258.2 grams.
Solution :
First we have to calculate the total heat absorbed.
where,
m = mass of water = 190 g
= specific heat of liquid water =
= enthalpy change for fusion of water =
= final temperature =
= initial temperature =
Now put all the given values in the above expression, we get:
Now we have to calculate the mass of substance.
As, 298 J of heat are absorbed by 1 g of
So, 76961.4 J of heat are absorbed by of
Therefore, the mass of this substance evaporate to freeze must be, 258.2 grams.