Breadcrumb navigation:
- Home
- > Subjects
- > NPA
- > NPA Science
- > Experimental Procedures (HN8D 46)
- > PracticalActivities
- > Chemistry Practical Activities
In this section
Chemistry Practical Activities
Examples of chemistry practical activities
Reaction rate
Suitable practical activity
An “iodine clock” practical where learners prepare a series of 5 reaction mixtures of known and varying concentrations to determine the rate vs concentration relationship by graphical analysis.
Reason why activity is suitable
Learners are required to:
- accurately prepare solutions by dilution
- taking accurate measurements
- achieve results demonstrating correct relationship
- conduct calculations and analysis/interpretation
- perform a suitable number of readings
Unsuitable practical activity
The time taken for pieces of magnesium ribbon to react with sulphuric acid of varying concentrations is measured to determine the effect of concentration on time of reaction.
Reason why activity is not suitable
- practical skills and accuracy not of suitable level
- lack of precise measurements
- lack of suitable interpretation/analysis
Volumetric
Suitable practical activity
The concentration of an unknown sodium hydroxide solution is determined by titration against known sodium hydroxide, using burette and pipette. Three replicates required.
Reason why activity is suitable
Learners are required to:
- correctly prepare and use analytical glassware
- take accurate measurements
- achieve results demonstrating accuracy
- conduct calculations and analysis/interpretation
- perform a suitable number of replicates
Unsuitable practical activity
Preparation of a standard solution of sodium carbonate. Known mass is dissolved and made to volume in volumetric flask. Portion is withdrawn (pipette) and diluted to volume in second flask.
Reason why activity is not suitable
- outcome of experiment is not measurable in terms of accuracy or correct performance
- lack of interpretation/analysis
- duration of activity is likely too short
Synthesis
Suitable practical activity
Synthesis of ester by reflux and its isolation by distillation using Quick Fit apparatus, with determination of yield.
Reason why activity is suitable
Learners are required to:
- assemble Quick Fit apparatus for each stage
- measure quantities of reactants and products
- determine % yield
Unsuitable practical activity
“Test tube” synthesis of ester.
Reason why activity is not suitable
- lack of complexity of equipment used
- lack of complexity in skill required
- inability to calculate yield
