c2

Cards (9)

what is the definition of a pure substance?
A pure substance is a single element or compound not mixed with any other substancePure elements will have specific melting and boiling points
what happens to an impure substance?
If a impure the melting point will be lower and the boiling point will be higher and vise versa
What is chromatography ?
Chromatography is used to separate mixtures of soluble compounds.
What is the stationary phase?
chromatography paper (doesn't move)
what is the mobile phase? 
solvent (moves)
how do you work out the rf
Rf= solvent/ solutionRf value should ALWAYS be between 0 and 1.
How are covalent bonds formed?
Covalent compounds are formed when NON METALS react together.Covalent bondings are where a pair of electrons are shared between 2 atoms
what are 5 things about metals
Malleable (able to be shaped)Have a high melting + boiling pointCan conduct electricityCan conduct heatAre strong
what are alloys?
A mixture of 2 elements when one is a metal which makes alloys harder than pure metals