lOMoARcPSD|59658805
2.1 calibration and standard solution write up
Biological science (University of Oxford)
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, lOMoARcPSD|59658805
Chester Ho 2.1:concentrate on keeping up your standard
Due: 5th October
2.1 Practical: calibrating and standard solution
Equipment list:
⚫ Top pan balance
⚫ Weight (100g, 200g, 300g, 400g)
⚫ Volumetric flask (250ml)
⚫ Volumetric pipette (25ml)
⚫ Burette (50ml)
⚫ Beakers (100ml, 250ml)
⚫ Funnel
⚫ Pipette (3ml, 25ml)
⚫ Thermometer
⚫ Weighting boat
⚫ Burette clamp
⚫ Distilled water
⚫ Anhydrous sodium carbonate
⚫ Stopper joint
⚫ Spatula
⚫ Hydrated copper sulfate
⚫ HCL
⚫ Sodium hydroxide
⚫ Colorimeter
⚫ PH meter
⚫ Phenolphthalein indicator
Introductions:
This practical write up involves calibrating equipments such as balance, volumetric
flask, pipette and burette to ensure everything is working properly in an acceptable
range of percentage error. Then we work on identifying concentration(molarity) of
HCL, NaCO while at last identifying concentrations of unknown sample through
colorimetry.
Calibrating the balance:
1. Turn on and take the top pan balance ensuring it is set to zero
2. Place 100g weight and record the value displaced
3. Repeat the second step for 3 more times with 100g added each time
4. Calculate the percentage error of the top pan balance
Downloaded by olinder seth ()
, lOMoARcPSD|59658805
Chester Ho 2.1:concentrate on keeping up your standard
Due: 5th October
Risk assessment: be careful about the weight and ensure this calibration is not done
on the edge of the table to prevent any injury due from the fall of weight, also a mat
underneath the weight can protect any surface being harmed.
(𝑢𝑛𝑐𝑒𝑟𝑡𝑎𝑖𝑛𝑡𝑦 𝑜𝑓 𝑡ℎ𝑒 𝑖𝑛𝑠𝑡𝑟𝑢𝑚𝑒𝑛𝑡 𝑥 100)
%𝑒𝑟𝑟𝑜𝑟 =
𝑇ℎ𝑒 𝑣𝑎𝑙𝑢𝑒 𝑚𝑒𝑎𝑠𝑢𝑟𝑒𝑑
The balance has an uncertainty of +/-0.1g
Results:
Actual mass (g) Measured mass (g) %error
100 99.90 (0.1x100)/99.90= 0.1001%
200 200.25 (0.1x100)/200.25=0.0499%
300 300.57 (0.1x100)/300.57=0.0333%
400 400.66 (0.1x100)/400.66=0.0249%
𝟎. 𝟏𝟎𝟎𝟏 + 𝟎. 𝟎𝟒𝟗𝟗 + 𝟎. 𝟎𝟑𝟑𝟑 + 𝟎. 𝟎𝟐𝟒𝟗
𝑴𝒆𝒂𝒏 𝒑𝒆𝒓𝒄𝒆𝒏𝒕𝒂𝒈𝒆 𝒆𝒓𝒓𝒐𝒓 =
𝟒
= 𝟎. 𝟎𝟓𝟐𝟎𝟓%
Evaluation: percentage error of this recorded result it acceptable as it is below 0.1%,
placing the weight on to the top pan balance
Downloaded by olinder seth ()
2.1 calibration and standard solution write up
Biological science (University of Oxford)
Scan to open on Studocu
Studocu is not sponsored or endorsed by any college or university
Downloaded by olinder seth ()
, lOMoARcPSD|59658805
Chester Ho 2.1:concentrate on keeping up your standard
Due: 5th October
2.1 Practical: calibrating and standard solution
Equipment list:
⚫ Top pan balance
⚫ Weight (100g, 200g, 300g, 400g)
⚫ Volumetric flask (250ml)
⚫ Volumetric pipette (25ml)
⚫ Burette (50ml)
⚫ Beakers (100ml, 250ml)
⚫ Funnel
⚫ Pipette (3ml, 25ml)
⚫ Thermometer
⚫ Weighting boat
⚫ Burette clamp
⚫ Distilled water
⚫ Anhydrous sodium carbonate
⚫ Stopper joint
⚫ Spatula
⚫ Hydrated copper sulfate
⚫ HCL
⚫ Sodium hydroxide
⚫ Colorimeter
⚫ PH meter
⚫ Phenolphthalein indicator
Introductions:
This practical write up involves calibrating equipments such as balance, volumetric
flask, pipette and burette to ensure everything is working properly in an acceptable
range of percentage error. Then we work on identifying concentration(molarity) of
HCL, NaCO while at last identifying concentrations of unknown sample through
colorimetry.
Calibrating the balance:
1. Turn on and take the top pan balance ensuring it is set to zero
2. Place 100g weight and record the value displaced
3. Repeat the second step for 3 more times with 100g added each time
4. Calculate the percentage error of the top pan balance
Downloaded by olinder seth ()
, lOMoARcPSD|59658805
Chester Ho 2.1:concentrate on keeping up your standard
Due: 5th October
Risk assessment: be careful about the weight and ensure this calibration is not done
on the edge of the table to prevent any injury due from the fall of weight, also a mat
underneath the weight can protect any surface being harmed.
(𝑢𝑛𝑐𝑒𝑟𝑡𝑎𝑖𝑛𝑡𝑦 𝑜𝑓 𝑡ℎ𝑒 𝑖𝑛𝑠𝑡𝑟𝑢𝑚𝑒𝑛𝑡 𝑥 100)
%𝑒𝑟𝑟𝑜𝑟 =
𝑇ℎ𝑒 𝑣𝑎𝑙𝑢𝑒 𝑚𝑒𝑎𝑠𝑢𝑟𝑒𝑑
The balance has an uncertainty of +/-0.1g
Results:
Actual mass (g) Measured mass (g) %error
100 99.90 (0.1x100)/99.90= 0.1001%
200 200.25 (0.1x100)/200.25=0.0499%
300 300.57 (0.1x100)/300.57=0.0333%
400 400.66 (0.1x100)/400.66=0.0249%
𝟎. 𝟏𝟎𝟎𝟏 + 𝟎. 𝟎𝟒𝟗𝟗 + 𝟎. 𝟎𝟑𝟑𝟑 + 𝟎. 𝟎𝟐𝟒𝟗
𝑴𝒆𝒂𝒏 𝒑𝒆𝒓𝒄𝒆𝒏𝒕𝒂𝒈𝒆 𝒆𝒓𝒓𝒐𝒓 =
𝟒
= 𝟎. 𝟎𝟓𝟐𝟎𝟓%
Evaluation: percentage error of this recorded result it acceptable as it is below 0.1%,
placing the weight on to the top pan balance
Downloaded by olinder seth ()
