# (solution) Names: __________________________ CHE111P Sec: _____ Worksheet

Names: __________________________ CHE111P
Sec: _____ Worksheet 4:_________
Material Balance (Single Unit) Questions 1. 100 kg of vinegar with strength of 4.63% wt acetic acid (HC 2H3O2) is to be
diluted to produce vinegar with strength of 4.00 % wt acetic acid.
a) Draw the process flowchart b) What is the tie component? _______________________
c) What is the most appropriate basis to answer also d and e?
_________________
d) Set-up a tie component balance using your basis and solve for the
unknown stream e) Calculate the weight of Water added using
i)
Overall material balance (OMB) ii) Component (water) balance f) If 100 kg of 4.00 % acetic acid will be prepared, how many kg of the
4.63 % acetic acid is needed? g) If 20 kg of water will be used, How many kg of the 4.63 % acid are
needed and how many kg of the product will be produced? 2. Tapioca flour is used in many countries for bread and similar products. The
flour is made by drying the course granules of the cassava root containing
66% wt moisture to 5% moisture and then grinding to produce flour. 5000
kg/h of flour will be produced.
a) Prepare a process flow chart and indicate the most appropriate
basis to answer the rest of the question. b) Using a tie component balance, determine the mass flow rate of
course granules to be dried. c) Calculate the mass flow rate of water removed. 3. A mill is extracting sugar from sugar beets (48% water, 40% pulp and 12%
sugar) using water as solvent. The residue from the process contains 25%
water, 70% pulp and 5% sugar. The sugar solution (extract) contains 15%
sugar.
a) Prepare a process flowchart b) Calculate the following if 1000 kg of beets were extracted
i. Using tie component balance, Calculate the mass of
residue produced ii. Using sugar balance, calculate the weight of the extract
stream. iii. amount of water used for the extraction 4. Wet sugar that contains one-fifth water by mass is conveyed through an
evaporator in which 85% of the entering water is vaporized. a) Prepare a process flow chart and indicate the most appropriate
basis to answer the rest of the question? b) Calculate the following ratio
i) Kg of product sugar leaving the evaporator per kg wet
sugar entering the evaporator ii) Kg of water vaporized per kg wet sugar entering the
evaporator iii) Kg water vaporized per kg of product sugar 5. A solution of potassium dichromate in water contains 13% by weight
K2Cr2O7. From 1000 lbs of this solution, 640 lbs of water are evaporated.
The remaining solution is cooled to 20oC. Calculate the amount of crystals
produced and the percentage recovery of K 2Cr2O7 crystals. Solubility of K2Cr2O7 at 20oC is 0.390 lb-mole per 1000 lb water.
a) Prepare a process flowchart and indicate the most appropriate
basis. b) Calculate the weight of crystal produced. c) Calculate the % recovery of K2Cr2O7 crystals. 