Chemical Analysis Flashcards
What are the four types of gases you can test for?
> Chlorine
Oxygen
Hydrogen
Carbon Dioxide
What is the test for Chlorine?
> Chlorine bleaches litmus paper, turning it white.
What is the test for Oxygen?
> Place a glowing splint inside a test tube containing oxygen, the oxygen will relight the glowing splint.
What is the test for Carbon Dioxide?
> Carbon Dioxide gas through an aqueous solution of calcium hydroxide (limewater) causes the solution to turn cloudy.
What is the test for Hydrogen?
> Hold a lit splint at the end of a test tube, if hydrogen gas is present a squeaky pop sound is heard.
What is a Pure Substance?
> A substance that contains one type of element or compound is deemed pure
How can you test for impurities?
> This is done via measuring the boiling and melting points of a given substance and compare it to the melting and boiling points of a pure substance and the closer this is to the actual melting and boiling points, the purer the substance.
Consequences of Impurities?
> Impurities in your sample will lower the melting points and increase the melting range.
Impurities can also increase boiling points resulting in your substance having boiling points at a range of temperatures
What is a Formulation?
> Useful mixtures with a precise purpose made following a formula. Each component is mixed in careful measured quantities in order to contribute to a specific function.
> Many products are complex mixtures in which each chemical has a particular purpose.
What are examples of formulations are there?
> Fuels, cleaning products, paints, medicines, alloys, fertilisers, foods and drinks
What is Chromatography?
> The physical separation technique which is used to separate substances in a mixture.
Used to identify substances
What two phases are there?
A mobile phase - where the molecules can move. (gas or liquid)
A stationary phase - where the molecule cannot move (solid or a thick liquid)
