c12

Question 1

mobile phase

Answer 1

gas or liquid that carries the component

Question 2

stationary phase

Answer 2

the part of the apparatus which doesn’t move with the sample

Question 3

test for hydrogen

Answer 3

a lighted wooden splint makes a popping sound in a test tube of hyrdogen

Question 4

test for oxygen

Answer 4

a glowing wooden splint relights in a test tube of oxygen

Question 5

test for carbon dioxide

Answer 5

carbon dioxide turns limewater cloudy

Question 6

test for chlorine

Answer 6

• sharp smell
• makes damp blue litmus paper turn red and then bleaches it white
• makes damp starch-iodide paper turn blue-black

Question 7

pure substances

Answer 7

made of only one type of atom or molecule

Question 8

how do you check if a substance is pure

Answer 8

by using the melting and boiling points

Question 9

the more impure a substance is…

Answer 9

…the higher the boiling point and it will boil over a range of temperatures

Question 10

formulations

Answer 10

• useful mixtures with a precise purpose that are made by following a ‘formula’
• each component in a formulation is present in a measured quantity

Question 11

pigment

Answer 11

gives the paint colour, for e.g. titanium oxide is used as a pigment in white paints

Question 12

solvent

Answer 12

used to dissolve the other components and alter the viscosity

Question 13

binder

Answer 13

forms a film that holds the pigment in place after its been painted on

Question 14

additives

Answer 14

added to further change the physical and chemical properties of the paint