Question

A 0.50 molar aqueous solution of hydrochloric acid (HCl) flows into a process unit at 25°C and a rate of 1.25 m3/min. If the specific gravity of the HCl solution is 1.03 at 25°C determine: a) HCl concentration in kg/m3 b) Mass flow rate in kg HCl/s c) MassfractioninkgHCl/kgsolution d) Mole ratio in mol HCl/mol water e) Molar flow rate in kmol HCl/s

Answer 1

Answer:

a) 18,23 kgHCl/m³

b) 0,38 kg HCl/s

c) 0,018 kgHCl/kgsolution

d) 8,75x10⁻³ molHCl/molH₂O

e) 0,010 kmolHCl/s

Explanation:

The HCl solution is 0,50 mol/L; it flows in a rate of 1,25 m³/min; Its density is 1,03 kg/L. HCl weights 36,46 g/mol

a) The HCl concentration in kg/m³ is:

$\frac{0,50molHCl}{L}$×$\frac{36,46gHCl}{mol}$×$\frac{1kg}{1000g}$×$\frac{1000L}{1m^3}$= 18,23 kg HCl/m³

b) As you have a concentration of 18,23 kgHCl/m³

$\frac{18,23 kgHCl}{m^3}$×$\frac{1,25m^3}{min}$×$\frac{1min}{60s}$ = 0,38 kg HCl/s

c) The mass fraction in kgHCl/kgsolution is:

$\frac{18,23kgHCl}{m^3}$×$\frac{1m^3}{1000L}$×$\frac{1L}{1,03kg}$ = 0,018 kgHCl/kgsolution

d) Supposing L of solution are just of water:

$\frac{0,50 moleHCl}{Lsolution}$×$\frac{1L}{1,03kg}$×$\frac{1kg}{1000g}$×$\frac{18,02gH_{2}O}{1mole}$= 8,75x10⁻³ molHCl/molH₂O

e) As the flow is 0,38kg HCl/s:

$\frac{0,38 kg}{s}$×$\frac{1kmole}{36,46kgHCl}$= 0,010 kmolHCl/s

I hope it helps!