You have been asked to design a heat exchanger to cool a fluid from 80°c to 50°c. the fluid has a mass flow rate of 2kg/s and a specific heat of 3500 j/(kg*k). you have chilled water as your heat transfer media, with an incoming temperature of 15c and a flow rate of 2.5kg/s. the overall heat transfer coefficient is 2000 w/(m2*k). a) calculate the area required for a crossflow, single pass heat exchanger, where both fluids are unmixed. b) calculate the area required for a concentric tube, parallel flow heat exchanger

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

hope this !