Hai everyone...Can anyone help me how 1.3g/L of Na2CO3 is calculated for 5% CO2. from the below reference took from research article.
****Reference****
The values of sodium carbonate concentrations corresponding to 5%, 10%, 15%, 20% and 30% CO2 concentrations at pH 7 are 1.3 g/L, 2.6 g/L, 3.8 g/L, 5.1 g/L, and 7.6 g/L, respectively.
****Reference****
The only difficulty here could be the conversion of volumetric %% of CO2 into the units of molarity. The key knowledge is the fact that under normal pressure and zero deg C, one mole of CO2 occupies a volume of 22.4 liters. At 25 deg C, it is about 24 liters (use the gas law to calculate the volume for your experimental conditions with required precision). 100% CO2 gas contains 1000 ml CO2 per liter of the gas phase. 5% CO2 mixture in air or N2 of whatever gaseous background, contains 50 ml per liter. If 24 ml CO2 is one millimole, then 50 ml is 50/24=2.08 mmol CO2. The final step is to convert 2.08 mmol to the equivalent amount of Na2CO3 xH2O. Do not forget to make corrections for the purity of your washing soda and the number of H2O.
Nicolai S Panikov Thanku so much sir...for your response...I tried to calculate the equivalent amount of Na2CO3...for me, it is coming as 0.22 grams...
But in reference, it is mentioned as 1.3 g/L...How 1.3 will come...Kindly help me, sir...
I am attaching the reference article here. I kindly request you to check the materials and methods part. Here they have given pH equation also....please help me to understand this..I am struggling with this part...Could not able to find..
Divya Ganesan I looked at the paper and another one (Upendar et al. 2018). The difference between your and their amounts of Na2CO3 could be from using different volumes of flasks. The exact amount of Na2CO3 without specifying other points is very strange, it is not professional. I would ignore this discrepancy, not everything published is correct! If you still have doubts, then just use any available gas analyzer: GC, IRGA, mass-spec, etc. As the last resort, if none is available in your laboratory, you can apply the 'ancient' method of absorbing CO2 with an alkali trap and titration. The dfference between 0.22 and 1.3 is more than 5 times! Also, you can take a pure compressed CO2 from a tank or from dry ice and inject 5 ml with a syringe into a 100 cc flask to have ~5%. Then you compare it with gas mixtures prepared from Na2CO3.