C12: Chemical analysis

Question 1

in chemistry what is a pure substance

Answer 1

something made of only one type of substance

Question 2

what is the difference between the melting and boiling points of a pure and impure substance

Answer 2

pure - sharp/one specific temperature
impure- broad/ occurs across a range of temperatures

Question 3

what is a formulation

Answer 3

a mixture designed for a specific purpose

Question 4

what are some examples of formulations

Answer 4

fuels, cleaning agents, paints, medicines, alloys, fertilisers, and foods

Question 5

what is chromatography

Answer 5

a process for separating coloured mixtures

Question 6

how is Rf calculated

Answer 6

Rf = distance moved by substance/ distance moved by solvent

Question 7

what is the test for hydrogen

Answer 7

a lit splint gives a squeaky pop

Question 8

what is the test for oxygen

Answer 8

re-lights a glowing splint

Question 9

what is the test for carbon dioxide

Answer 9

turns lime water milky if bubbled through it

Question 10

what is the test for chlorine

Answer 10

bleaches damp litmus paper