Question
(c) A.student used a pipette to add 25.0cm^3 of sodium hydroxide of unknown concentration to a conical flask The student carried out a Stration to find out the volume of 0.100mol/dm^2 acid needed to neutralise the sodium hydroxide Describe how the student would complete the titration You should name a suitable indicator and give the colour change that would be seen __ (d) The student carried five titrations. Her results are shown in the table below. Concordant results are within 0.10cm^3 of each other. Use the student's concordant results to work out the mean volume of 0.100mol/ dm^3 sulfuric acid added. __ (4)
Answer
3.8
(247 Votes)
Felicity
Master · Tutor for 5 years
Answer
## Step 1: Identify the Concordant ResultsThe concordant results are 27.05, 27.15, and 27.15.## Step 2: Calculate the Mean VolumeThe mean volume is calculated as follows:###
Therefore, the mean volume of
sulfuric acid added is approximately 27.12
.
Explanation
## Step 1: Identify the Concordant ResultsFirst, we need to identify the concordant results from the table. Concordant results are those that are within
of each other. From the table, we can see that the volumes of sulfuric acid in Titration 3, 4, and 5 are within
of each other. These are 27.05, 27.15, and 27.15 respectively.## Step 2: Calculate the Mean VolumeNext, we calculate the mean volume of the concordant results. The mean is calculated by adding up all the values and then dividing by the number of values. ### The formula for mean is: **
**## Step 3: Apply the Mean FormulaWe apply the mean formula to the concordant results.