How many grams of liquid sodium.. HELP!!

Question

Liquid sodium is being considered as an engine coolant. How many grams of liquid sodium (minimum) are needed to absorb 9.20 MJ of energy (in the form of heat) if the temperature of the sodium is not to increase by more than 10.0 C? Use Cp=30.8 J/(K*mol) for Na(l) at 500 K.

Answer 1

Heat generated=Heat Capacity*Change in Temperature

 

9,200, 000 J=9.20 MJ (Multiply 9.20 * 1,000,000)

 

9,200,000=30.8 J/K*mol *# moles* (10 K), 10K is change in temperature

 

9,2000,000/(30.8*10) moles=# moles Na heated.

 

 

 

29, 870 moles of Na are heated

 

#grams of Na=29,870 moles *(22.99 g Na/mole)

 

#grams=686714.28 grams Na heated