Question

Liquid toluene is flowing through a pipe at a rate of 175 m 3 / h 175m3/h . What is the mass flow rate of this stream in kg/min? What is the molar flow rate in mol/s? In fact, the answer to Part (a) is only an approximation that is almost certain to be slightly in error. What did you have to assume to obtain the answer?

Answer 1

(a) Mass flow rate is 2528.75 kg/min

(b) Molar flow rate is 458.1 mol/s

(c) Toulene is in-compressible at standard temperature and pressure

Step-by-step explanation:

The volume flow rate of liquid toulene is given:

Volume Flow Rate = 175 m^3/h

Density of Liquid Toulene = 867 kg/m^3

Molar mass of Toulene = 92 g/mol = 0.092 kg/mol)

(a)

Thus, the mass flow rate of toulene will be:

Mass Flow Rate = (Volume Flow Rate)(Density)

Mass Flow Rate = (175 m^3/h)(867 kg/m^3)

Mass Flow Rate = (151725 kg/h)(1 h/60 min)

Mass Flow Rate = 2528.75 kg/min

(b)

Now, for molar flow rate we use formula:

Molar Flow Rate = (Mass Flow Rate)/(Molar Mass)

Molar Flow Rate = (2528.75 kg/min)/(0.092 kg/mol)

Molar Flow Rate = (27486.41 mol/min)(1 min/60sec)

Molar Flow Rate = 458.1 mol/s

(b)

The assumption is that Toulene is in-compressible at standard temperature and pressure. So, that its density can be taken constant.