# Standardisation of Hydrochloric Acid Report

Topics: Chlorine, Measurement, Mole Pages: 3 (524 words) Published: August 25, 2013
STANDARDISATION OF HYDROCHLORIC ACID REPORT

Aim:
To standardize an unknown solution of hydrochloric acid

Method:
See INSTRUCTIONS for practical 6.2 & 6.3

Results:

Attempt No.| Titre (mL)| |
1| 20.9| Rough Titration|
2| 20.5| |
3| 20.7| Concordant Titres|
4| 20.7| |
5| 20.7| |
(1) Tabled Results

(2) Concordant Titrations Results

20.7 mL|
20.7 mL|
20.7 mL|
Average of Concordant:
(20.7 + 20.7 +20.7) 3= 20.7 mL

Calculations:
(1) Equations a) Titration of HCl with Sodium Carbonate:
Na2CO3 + 2HCl 2NaCl + H2O + CO2

(2) Concentration of Sodium Carbonate (Na2CO3)
Molar mass of Na2CO3: 22.99*2+12.01+16*3=105.99
Mass of Na2CO3: 1.3 g
Number of moles :
n=mM
=1.3 105.99=0.012265308 mol
Volume Na2CO3 solution: 250 mL
: 0.250 L
Concentration:
Concentration of Sodium Carbonate is 0.049 mol L-1
c=nV
= 0.012265308 0.250=0.049061232 mol L-1

(3)Concentration of HCl
Volume of Na2CO3 solution: 20 mL
: 0.020 L
Number of moles of Na2CO3:
n=C x V
=0.049 x 0.020
=0.00098 mol
Volume of HCl: 20.7 mL (average of concordant result based on titration)
: 0.0207 L
Number of moles of HCl:
Stoichiometric Ratio between Na2CO3 and HCl:
21 (From equation above)

nHCl =2 x nNa2CO3
=2 x 0.00098=0.00196 mol
Concentration:
Concentration of Hydrochloric Acid is 0.095 mol L-1
CHCl=nHClV
= 0.00196 0.0207 =0.0946859903 mol L-1

Analysis & Evaluation:
(1) Conclusion
The concentration of the Hydrochloric acid is known to be 0.10 mol L-1 (2) Random Errors
Random errors are chance variations between successive measurements over which the experimenter has little or no control. They are linked to the precision of the measurements. Possible random errors that occur during the experiment may include:...