chemical analysis

Question 1

pure substance:

Answer 1

contains only 1 type of element
or
contains only 1 type of compound

Question 2

pure substances…..

Answer 2

• melt + solidify at 1 temp

- boil + condense at 1 temp

Question 3

impure substances are

Answer 3

mixtures

Question 4

impure substances….

Answer 4

• do not melt or boil at 1 temp

- change state over a range of temperatures

Question 5

formulations=

Answer 5

mixtures that have been carefully designed to have specific properties

Question 6

chromatography involves:

Answer 6

• stationary phase (doesn’t move)

- mobile phase (moves)

Question 7

paper chromatography:

Answer 7

• stationary phase (absorbent paper)

- mobile phase (solvent-water)

Question 8

chromatography use:

Answer 8

used to identify artificial colours

Question 9

Rf values are used…

Answer 9

to identify the components in a mixture

Question 10

Rf=

Answer 10

distance moved my substance
——————————————
distance moved by solvent

Question 11

gas test

Hydrogen:

Answer 11

lit splint in test tube

squeaky pop

Question 12

gas test

chlorine:

Answer 12

blue litmus paper goes red then bleached white

Question 13

gas test

oxygen:

Answer 13

glowing splint relights

Question 14

gas test

carbon dioxide:

Answer 14

lime water goes cloudy