Chemical Analysis Flashcards
what is meant by a pure substance?
something that only contains one compound or element
how can you test for the purity of a substance?
measuring its melting/boiling point and comparing it to the melting/boiling point of a chemically pure substance
what will impurities in your sample do to the melting/boiling point of your substance?
lower melting point
increase boiling point
what are formulations?
useful mixtures with precise purpose that are made by following a formula
what is the test for chlorine?
bleaches damp litmus paper white
what is the test for oxygen?
if you put a glowing splint inside a test tube containing oxygen it will relight
what is the test for carbon dioxide?
bubbling carbon dioxide with limewater turns the solution cloudy
what is the test for hydrogen?
if you hold a burning splint at the end of a tube containing hydrogen you will hear a squeaky pop
what is chromatography?
an analytical method used to separate the substances in a mixture
what is a mobile phase?
where the molecules can move
what is a stationary phase?
where the molecules cannot move
what is the result of chromatography called?
a chromatogram
how do you calculate the rf value?
distance travelled by the substance divided by distance travelled by the solvent
