Chemical Thermodynamics Question 364
Question: $ 36mL $ of pure water takes 100 sec to evaporate from a vessel and heater connected to an electric source which delivers 806 watt. The $ \Delta H_{vap} $ of $ H_2O $ is:
Options:
A) $ 40.3kJ/mol $
B) $ 43.2kJ/mol $
C) $ 4.03kJ/mol $
D) None of these
Show Answer
Answer:
Correct Answer: A
Solution:
- 1 watt = 1 J/sec Total heat supplied for $ 36mL,H_2O $
$ =806\times 100 $
$ =80600J $
$ \Delta H_{vap}=\frac{80600}{36}\times 18 $
$ =40300Jor40.3kJ/mol $