Q1. (7) The solubility of sodium sulfate is 40 parts Na2SO4 per 100 parts of water at 30°C, and 13.5 parts at 15°C. The latent heat of crystallization (liberated when crystals form) is 18,000 g-cal per gmol Na2SO4. Glauber's salt (Na2SO4-10H2O) is to be made in a Swenson-Walker crystallizer by cooling a solution, saturated at 30°C, to 15°C. Cooling water enters at 10°C and leaves at 20°C. The over-all heat transfer coefficient in the crystallizer is 25 BTU/h ft2 °F and each foot of crystallizer has 3 sq ft of cooling surface. How many 10-ft units of crystallizer will be required to produce 1 ton/h of Glauber's Salt Conversion factors and other information: 1 ton-2000 lb 1°C=1.8 °F Molar mass of Glauber's salt - 322 g/mol 1 lb 454 g I BTU 252.16 cal F 1-30 C -30 C Cp 0.7803 BTU/lb."F W SWENSON-WALKER CRYSTALLIZER L 15 C 1-10 C 6=20°c C, 1 ton/h Na,SO, 10H,O -15 C