Chemical Analysis Flashcards
What are some qualities of pure substances?
They melt and solidify at one temperature.
The boil and condense at one temperature.
What aree formulations?
Mixtures that have been carefully designed to have specific properties.
What are some examples of formulations?
Fuels, cleaning agents, paints, medicines, alloys, fertilisers and foods.
What is the stationary phase in chromatography?
Where is doesn’t move.
What is the mobile phase in chromatography?
Where is does move.
What is the mobile and stationary phase in paper chromatography?
The stationary phase is the absorbent paper.
The mobile phase is the solvent (usually water).
What happens during chromatography?
Mixtures get separated into their constituent components.
How can different components be seen in chromatography?
As the solvents dissolve up the paper, each component is left at a different distance on the paper depending on its attraction for the paper and for the solvent.
What can chromatography be used for?
Identifying artificial colours (like in food).
What are R*1 values used for?
To identify the components in a mixture.
How can you calculate R*1 values?
(distance moved by substance) / (distance moved by solvent)
How can one test for hydrogen?
When mixed with air, it burns with a squeaky pop.
How can one test for oxygen?
The gas relights a glowing splint.
How can one test for chlorine?
Bleaches damp litmus paper white.
How can one test for carbon dioxide?
When bubbled through limewater, this solution turns cloudy.
