C14 Chemical Analysis Flashcards
What do impurities do to the melting and boiling points of a sample?
Lower the melting point and raise the boiling point
What is a formulation?
Mixtures that contain specific measured quantities of elements/compounds to ensure efficacy in their usage
What are the 2 phases of chromatography?
-Mobile- molecules can move
-Stationary- molecules can’t move
How can Rf values be calculated?
Distance travelled by the the substance/distance between solvent front and baseline
What conditions can affect the time a substance spends in the mobile phase?
The type of solvent used
What is the stationary phase in paper chromatography?
The chromatography paper
(chromatography) The longer a substance spends in the _______ phase, the further it moves up the paper
Mobile
What is the test and positive result for chlorine?
Holding damp litmus paper up to the reaction vessel- bleaches it white
What is the test for hydrogen?
Produces a ‘squeaky pop’ when a lit splint is held to it
What is the test for oxygen?
Relights a glowing splint
What is the test for carbon dioxide?
Turns lime water cloudy when bubbled through it
What is lime water?
Calcium carbonate solution
How can a sample be tested for metal ions using a flame?
Dip a nichrome wire in hydrochloric acid and hold it in a blue flame in a Bunsen burner. Withdraw it when no colour is produced. Dip into the sample and hold it into the flame to observe the colour.
Why may testing for ions by observing the colour of the flame they produce be unreliable?
If the sample contains multiple metal ions, the flame colours of some may be obscured by the others.
What colour flame do lithium ions produce?
Red
