the concentration of solutions
Contents
Glossary.............................................................................................................................................1
Titration (sodium hydroxide).................................................................................................................2
Title....................................................................................................................................................2
Introduction.......................................................................................................................................2
Method..............................................................................................................................................2
Results...............................................................................................................................................4
Analysis..............................................................................................................................................5
Apparatus errors/ uncertainty...........................................................................................................6
Conclusion.........................................................................................................................................8
Steps to ensure accuracy.................................................................................................................10
Equipment list..................................................................................................................................11
Titration (sodium carbonate)...............................................................................................................12
Title..................................................................................................................................................12
Introduction.....................................................................................................................................12
Method............................................................................................................................................12
Results.............................................................................................................................................12
Risk assessment...............................................................................................................................12
Analysis............................................................................................................................................15
Apparatus uncertainty.....................................................................................................................16
Conclusion.......................................................................................................................................18
Steps to ensure accuracy.................................................................................................................19
Colorimetry..........................................................................................................................................20
Title..................................................................................................................................................20
Introduction.....................................................................................................................................20
Method............................................................................................................................................20
Results.............................................................................................................................................21
Analysis............................................................................................................................................22
Risk assessment...............................................................................................................................24
Conclusion.......................................................................................................................................25
Steps to ensure accuracy.................................................................................................................27
References...........................................................................................................................................28
, Unit 2 Standard Solutions Report Assignment A
Glossary
Word Definition
Titration The process of determining the concentration of an unknown
solution using a solution of known concentration.
Precision How close two or more measurements are to each other.
Ambient The temperature of the surroundings
temperature
Drifting Variations in the readings of the balance due to internal mechanical
wear, for example.
Quantitative Practical experiment producing numerical results (quantities are
analysis measureable)
Qualitative Practical experiment producing observational results such as colour,
analysis odour, transparency.
Absorbance A measure of the amount of light of a particular wavelength which
is absorbed by a sample.
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, Unit 2 Standard Solutions Report Assignment A
Titration (sodium hydroxide)
Title
Making a standard solution of sodium hydroxide (NaOH) to use to find the
concentration of hydrochloric acid (HCl) using titration.
Introduction
A standard solution of sodium hydroxide was made and then titrated against a
sample solution of hydrochloric acid to determine the accurate concentration of the
acid.
HCl + NaOH à NaCl + H2O
Method
• I am are going to make a 0.2mol dm-3, 100cm3 solution of NaOH
• To do this I need to add an accurate mass of solid NaOH and dilute with distilled
water up to the meniscus of the volumetric flask line. Put a small beaker on the
weighing balance and press the tare button to zero it.
• Use a spatula to add 0.8g to the beaker and my mass was 0.84g. Add a small
amount of distilled water and begin to dissolve the NaOH using a glass stirring rod
• Add insignificant amounts of water until it has fully dissolved. When it has
dissolved, add a funnel to the volumetric flask and pour in the contents from the
beaker
• I must then rinse the stirring rod with distilled water, catching the water into the
beaker, add this to the volumetric flask
• Add some more distilled water to the beaker and swirl. Add this to the volumetric
flask. Add distilled water to the flask until the meniscus is on the line
• Fill the volumetric flask with distilled water up to the graduated mark, carefully
using a pipette to ensure the meniscus is on the line.
• Stopper the volumetric flask and invert the flask and its contents 20 times to mix.
• Pour the volumetric flask contents into the empty large beaker with the blue label
• This is my NaOH solution to use in the next titration
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