1b elements compounds and mixtures

Question 1

element

Answer 1

​substance​ ​made​ ​from​ ​only​ ​one​ ​type​ ​of​ ​atom

Question 2

compound

Answer 2

substance​ ​made​ ​from​ ​two​ ​or​ ​more​ ​elements​ ​that​ ​have​ ​reacted chemically​ ​with​ ​each​ ​other

Question 3

mixture

Answer 3

o Consists​ ​of​ ​2​ ​or​ ​more​ ​elements​ ​or​ ​compounds​ ​not​ ​chemically​ ​combined
together
o Chemical​ ​properties​ ​of​ ​each​ ​substance​ ​in​ ​the​ ​mixture​ ​are​ ​unchanged

Question 4

pure substance

Answer 4

​a​ ​single​ ​element​ ​or​ ​compound,​ ​not​ ​mixed​ ​with​ ​any​ ​other substance

Question 5

simple distillation

Answer 5

Used​ ​to​ ​separate​ ​a​ ​pure​ ​liquid​ ​from​ ​a​ ​mixture​ ​of​ ​liquids
▪ Works​ ​when​ ​the​ ​liquids​ ​have​ ​different​ ​boiling​ ​points
▪ Commonly​ ​used​ ​to​ ​separate​ ​ethanol​ ​from​ ​water

Question 6

fractional distillation

Answer 6

used to separate the complex mixture into fractions that contain similar boiling points

Question 7

Filtration

Answer 7

normally used to separate an insoluble substance from a liquid using filtration paper

Question 8

Crystallisation

Answer 8

▪ You​ ​would​ ​first​ ​warm​ ​the​ ​solution​ ​in​ ​an​ ​open​ ​container,​ ​allowing the​ ​solvent​ ​to​ ​evaporate,​ ​leaving​ ​a​ ​saturated​ ​solution
▪ Allow​ ​this​ ​solution​ ​to​ ​cool
▪ The​ ​solid​ ​will​ ​come​ ​out​ ​of​ ​the​ ​solution​ ​and​ ​crystals​ ​will​ ​start​ ​to
grow,​ ​these​ ​can​ ​then​ ​be​ ​collected​ ​and​ ​allowed​ ​to​ ​dry

Question 9

paper chromatography

Answer 9

used to separate dyes