A steam rocket is a device in which a liquid is enclosed in a pressure-resistant container water. The water is heated above its normal boiling point and the rocket another the head is opened. Now water clearly hotter than the boiling point forms gas, which, when discharged, propels the rocket into motion.

a)

What is the maximum water temperature if the pressure resistance of the container is 13 bar? We can use  for water's 

where and

b)

How much of the water is gasified, if the temperature of the exiting gas can be assumed 100 C and heat capacity 0.079 kJ/molK ?

Hint: For vaporization the necessary energy is obtained from the cooling water mass.