Development of practical skills Flashcards
(9 cards)
How should you read from a burette?
From the bottom of the meniscus at eye-level against a constant background.
This ensures accuracy in measurement.
How should burette measurements be recorded?
To 2 decimal places and should end in 0 or 5.
The mean titre does not have to end in 5 or 0.
What should be done near the endpoint of a titration?
Add the solution dropwise.
How should you perform mean titres?
Repeat titrations until there are two concordant titres (within 0.10 cm3) and take an average of the concordant titres. Round to 2 d.p. if required.
By what 4 ways can you heat reactions?
- Water bath
- Electric heater
- Sand bath
- Bunsen burner
By what 2 ways can you purify products?
- Solids by recrystallisation
- Liquids by separating funnel or distillation
What are the 2 types of errors?
- Random (eliminated by repeating)
- Systematic
Give 3 examples of readings.
Examples of readings include:
* Burette measurement
* Thermometer reading
* pH meter reading
Give 3 examples of measurements.
Examples of measurements include:
* Volume of liquid
* Mass of solid
* Temperature of solution
