Chemical analysis-Chemistry paper 2 Flashcards
Define formulation
It is a mixture that has been designed to produce a useful product.
What is meant by impurity?
This is where there is another substance that makes a pure substance impure.
Define insoluble
A substance that does not dissolve in a solvent.
Define soluble
A substance that dissolves in a solvent.
Define solvent
the liquid that can dissolve a solute into it.
what is meant by the term precipitate?
This is the solid that is produced froma reaction.
what is a positive ion?
An atom that has lost electrons to form positive ions.
what is a negative ion?
An ion that has gained electrons to form a negative charge.
What is the retention factor in chromotography?
It is a measurement from chromotography, it is the distance that a spot of substance has been carried above the baseline divided by the distance of the solvent front.
What is the test for oxygen?
If oxygen is present it relights a glowing splint.
What is the test for hydrogen?
If hydrogen is present it makes a squeaky pop with a glowing splint.
What is the test for carbon dioxide?
if carbon dioxide is present then it turns limewater cloudy.
how do we calculate the rf value?
The distance moved by substance divided by the distance moved by solvent.
What do metal hydroxides appear as if they are insoluble?
They appear as precipitates.
Different metals from diffeerent coloured precipitates when reacted with sodium hydroxide.
What precipitate do each of these metal ions form?
1.) Aluminimum
2.) Calcium
3.) magnesium
4.) Copper
5.) Iron(2)
6.) Iron(3)
1.) white
2.) white
3.) white
4.) blue
5.) green
6.) brown
How is a formulated product formed?
it is formed by mixing the components in carefully measured quantities to ensure that the product has the required properties.
Different halides produce different coloured insolubleprecipitates when reacted with silver ions.
What precipitate colur do these halide ions form?
1.) Chlorine
2.) Bromide
3.) Iodide
1.) white
2.)cream
3.)yellow
What is the flame test method how is it performed?
The flame test methods identify different metals because they produce different colours.
The method is performed by dipping a wire loop into a sample then placing into the blue flame of a bunsen burner.
What colours do these metals show if they are presnt in a flame test?
1.) Sodium
2.) Potassium
3.) Calcium
4.) Copper
5.) Chromium/Lithium.
1.) yellow
2.) Lilac(purple)
3.) calcium(orange/red)
4.) blue
5.) crimson red
How do you test for carbonates? and prove carbon dioxide is pesent?
Carbonate ions react with a dilute acid such as hydrochloric acid and produce carbon bubbles.
The gas can be collected and passed through limewater to prove that it is carbon dioxide.
How do you test for sulfates
Suldate ions react with barium chloride (when acidified) to produce insoluble barium sulfate.
