A level Chemistry OCR B Salters - Development of practical skills flashcards

1 - Development of practical skills worth at least 15%
or more of total exam marks from the specification

1.1.1 - 1.1.4 Planning| Implementation |Analysis| Evaluation|
skills assessed in a written examination

Give 4 examples of readings and 4 Reading
examples of measurements? ● Thermometer
● pH meter
● balance
● Measuring cylinder
● Volumetric flask
Measurement
● Ruler
● Stopwatch
● Analogue meter
● burette

What are the 2 types of errors? 1. Random (eliminated by repeating)
2. Systematic

What are standard solutions? A solution for which its concentration is known
accurately

What 3 things should you ensure when 1. Ensure you have clean dry equipment
making standard solutions? 2. Make washings to remove any salt BEFORE
MAKING up the solution to the specified amount
3. Invert the volumetric flask to ensure everything is
dissolved

Give 2 ways of improving an experiment 1. Let the reaction carry on until the gas syringe has
that uses a gas syringe? stopped moving
2. Wait for the gas to cool to room temperature before
reading

There is no point writing 0.150 mol dm-3.
Writing 0.15 mol dm-3 means the same
thing.
● The student is incorrect (1)
● 0.150 means between 0.1495 and 0.1504

IGNORE reference to significant figures