Water at 4^◦C has a density of 1000 kg/m³. What is the equivalent value in units of
a. g/cm³?
b. lbm/ft³?
c. gmol/L? (as used in Example 4.5)

EXAMPLE 4.5 SOLUTION For the acid-neutralization problem, the volumetric flow rate of the HCI solution coming from our manufacturing process is 11,600 L/hr, and the average concentration of HCI in that stream is 0.014 M, or 0.014 gmol/L. Based on this information and the answers in Example 4.4, a. How many gmol of HCI are in 88 m of the solution? b. How many gmol of HCI are flowing from the process per minute (i.e., what is the molar flow rate) when the volumetric flow rate of the solution is 11,600 l/hr? c. What is the mass fraction of HCI in the solution? a. Manipulating the definition of concentration, 0.014 gmol L nHCI=CHCIV = b. From Equation 4.6b, 0.014 gmol L c. From the definition of mass fraction, HCI = CHCIV = ) (88 m) (- XHCI = ) ( =) ( 11,600 L hr XHCI = 1000L m I m 1 hr 60min MWHCHCI m = 1,232 gmol HCI Atomic weights are listed in the front of the book, giving MWHCI= 1.0+ 35.5 = 36.5 g HCV/gmol, and m is available from Example 4.4, so (36.5 g HCl/gmol) (2.71 gmol HCl /min) 11,600kg /hr = 2.71 gmol HCl /min 1kg 1000 g 60min 1 hr = 0.00051