Core practical - Chromatography (AQA GCSE Chemistry): Quizzes
📚Quizzes
Practise the questions
12 questions from this quiz
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Practise the questions
12 questions from this quiz
What is the main aim of paper chromatography?
What is the main aim of paper chromatography?
To identify substances in a mixture
What is the stationary phase in chromatography?
What is the stationary phase in chromatography?
The paper that stays still
What is the mobile phase in chromatography?
What is the mobile phase in chromatography?
The solvent that moves up the paper
Why do different substances separate in chromatography?
Why do different substances separate in chromatography?
They are attracted to phases differently
Why must you use pencil, not pen, to draw the start line?
Why must you use pencil, not pen, to draw the start line?
Pen would interfere with results
What must never happen to the pencil line during setup?
What must never happen to the pencil line during setup?
It must not go below the solvent level
How can you tell if a substance is pure using chromatography?
How can you tell if a substance is pure using chromatography?
It makes only one spot
What should you mark when the solvent has finished moving up the paper?
What should you mark when the solvent has finished moving up the paper?
Where the solvent stopped
What is an Rf value used for?
What is an Rf value used for?
To identify what a substance is
What is the range of possible Rf values?
What is the range of possible Rf values?
Always less than 1
A substance travels 45mm and the solvent travels 90mm. What is the Rf value?
A substance travels 45mm and the solvent travels 90mm. What is the Rf value?
0.50
The solvent travels 80mm. A spot travels 64mm. Calculate the Rf value.
The solvent travels 80mm. A spot travels 64mm. Calculate the Rf value.
0.80