First working out the number of moles from the burette
Moles = c × vdm3
C = 0.1, v = 0.0239
Moles = 0.1 × 0.0239 = 2.39 ×10-3
Step 2 working out the Concentration of NaOH in the flask
C = mole ÷ v dm3
V = 25 cm3 ÷ 1ooo =0.025dm3
C = 2.39 ×10-3 ÷ 0.025 = 0.0956 moledm3
The strongest and weakens of the experiment.
During the experiment there are some of the human error that occurred , which include reading the burette wrong or adding the wrong amount of Hcl solution ,this lead us to get a different results .
This error could improve by making sure reading the practical hand out and fellow the experiment steps carefully.
In addition some of us they didn’t add the exact amount of Indicator (Phenolphthalein).So when they titrated with Hcl also added more than they need, therefore this affect the accurately of the result they didn’t observe any colour change.
This error could be improved by making sure adding the exact amount of indicator or Hcl.
A further weakness was that when the pipette filler was used on the pipette it was very hard to fill the pipette with NaOH and the air bubbles was in side of the pipette. This affected the accuracy of the result and the experiment was take long time to finish.
To improve this error we should use alternative method or more developed pipette filler this because to get accurate result at less time.
Percentage errors
Calculate the percentage error in a 25mL pipette:
25mL pipette is 0.6mL
% = 0.6 /25 × 100 = 2.4%
Calculate the percentage error in burette reading is 0.05:
% error = 0.05/23.90 × 100 = 0.21% to 2dp
0.21 + 2.4% = 2.61%
The method of collecting this data would be completely different if I used data logging in this experiment. These because the data logging system its set up to monitor a process using sensors linked to a computer .Most data logging can be done automatically under computer control. But the collecting data by humans will be done manually.
If we used data logging the measurements are always taken at the right time, and the computer will not forget to take a reading or take late reading but the human unlike.
The data logging software will store the readings in a table and the data can later be analysed using graph tools automatically. The report can then be saved and widely distributed in different ways such as email, post and fax. While the manual it’s difficult to pass to an or send it by email or fax and also it will be takes long time to pass.
Using data logging equipment can take reading the results with high of accuracy and also can be less human error. In addition we can take many readings in a short of time during data logging is used. However, humans can make errors when taking the reading. Also the equipment that used with data logging is different from those in collecting manual data. This equipment used to monitor water levels would have to be waterproof for example so its need to be very robust
