A 20 wt % solution of sulfuric acid in water is to be enriched to a 60 wt % sulfuric acid solution by adding pure sulfuric acid. a. How much pure sulfuric acid should be added? b. If the 20 wt % solution is available at 5◦C, and the pure sulfuric acid at 50◦C, how much heat will have to be removed to produce the 60 wt % solu- tion at 70◦C? How much heat will have to be added or removed to produce the 60 wt % solution at its boiling point?

Amixture of slurry and mud is to be pumped through a horizontal pipe of diameter 500 mm. the fluid behaves as a bingham plastic with a yield stress of 30 pa and viscosity 0.04 pa.s. describe the effects of the shear stress through a transverse section of the pipe by plotting the variation in shear stress and velocity profile: (i) just before the slurry starts to move (ii) as the slurry flows when the pressure gradient is double that in part (i)