Equilibrium value for carbonation level in beer

Click For Summary
SUMMARY

The equilibrium value for carbonation level in beer is calculated to be 3.752 g/L based on the application of Henry's Law, where the pressure (P) is determined to be 1.3432 atm. This pressure is derived from the sum of gauge pressure (0.0987 atm), atmospheric pressure (1 atm), and hydrostatic pressure (0.2445 atm). The calculation involves converting pressures from pascals to atmospheres and determining the concentration (C) of CO2 in mol/L. It is important to note that significant figures should be carefully considered, with the final answer being accurate to ±5% due to the precision of the input values.

PREREQUISITES
  • Understanding of Henry's Law and its application in gas solubility
  • Knowledge of pressure units, specifically conversion between pascals and atmospheres
  • Familiarity with basic hydrostatics and the calculation of hydrostatic pressure
  • Ability to perform calculations involving significant figures and precision
NEXT STEPS
  • Research the implications of Henry's Law in beverage carbonation processes
  • Explore the effects of temperature on gas solubility in liquids
  • Learn about the significance of significant figures in scientific calculations
  • Investigate methods for measuring carbonation levels in beer using pressure sensors
USEFUL FOR

Brewers, beverage scientists, and anyone involved in the production and quality control of carbonated beverages will benefit from this discussion, particularly those interested in the chemical principles governing carbonation levels.

sci0x
Messages
83
Reaction score
5
Homework Statement
A beer is matured in a vessel at 5 degrees. The vessel has diameter of 5m. Top pressure is 0.1 bar g CO2. Fill level is 100%. Calculate equilibrium value for average carbonation level in beer in g/L.

Data: Atm pressure = 101.3kPa
Henrys constant for CO2 in beer at 5 deg C = 15.75 atm litre mol-1
Acc due to gravity = 9.81 ms-1
Beer density at 5 deg = 1010 kg m-3
Mol mass of CO2 = 44 g mol-1
Relevant Equations
Absolute pressure = Gauge press + Atm press + Hydrostatic press
Abs Pressure:
Gauge press: 1 bar G = 100,000 Pa = 0.987 atm
0.1 bar G = 0.0987 atm

Atm press = 101.3 kPa = 1 atm

Hydrostatic press: average CO2 occurs 2.5m up the vessel
(9.81 ms-2)(1010kgm-3)(5/2) = 24,770.25 Pa
1 Pa = 9.869x10^-6 atm
24,770.25 Pa = 0.2445 atm

Abs press= 0.0987 atm + 1 atm + 0.2445 = 1.3432 atm

Henrys Law: P = KhC
1.3432 atm = 15.75 atm litre mol-1 C
C = 0.0853 mol-1 / L

44g CO2 in 1 mole
3.752g CO2 in 0.0853 mol-1 / L

Equilibrium value = 3.752 g/L

Am i correct here please?
 
Physics news on Phys.org
It looks to me like your approach was correct. I haven't checked the arithmetic, however.
 
  • Like
Likes   Reactions: sci0x
sci0x said:
mol-1 / L
You mean mol/L, right?
As a matter of style, there are many benefits in working entirely symbolically, only plugging in numbers at the final step.
Also, you cannot justify that many significant digits in the answer. Some values are only given to one sig fig, but then there is the complication of adding the gauge pressure to atmospheric, which makes keeping track of the precision tricky. Looks like the final answer can only be claimed ±5%.
 
Last edited:
  • Like
Likes   Reactions: sci0x

Similar threads

Replies
12
Views
2K
  • · Replies 4 ·
Replies
4
Views
1K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
Replies
1
Views
16K
  • · Replies 4 ·
Replies
4
Views
8K
Replies
4
Views
4K
  • · Replies 3 ·
Replies
3
Views
8K
Replies
4
Views
3K
  • · Replies 1 ·
Replies
1
Views
5K