C9

Question 1

What are chemically pure substances?

Answer 1

Substances that have exact and specific melting points and are made up of one element or compound

Question 2

What do impurities do?

Answer 2

Widen the range of temperature a substance melts and boils

Question 3

Stage 1 of paper chromatography

Answer 3

Dip the bottom of chromatography paper in solvent

Question 4

Stage 2 of paper Chromatography

Answer 4

As solvent moves up it transports the substances being tested on the paper

Question 5

Stage 3 of Paper Chromatography

Answer 5

The substances that travel furthest are the most soluble and are minimally attracted to the chromatography paper

Question 6

Rf value calculatiob

Answer 6

Distance travelled by substance/distance travelled by solvent

Question 7

Magnesium, Calcium and Aluminium form what colour precipitate?

Answer 7

White

Question 8

Copper (II) precipitate is

Answer 8

Blue

Question 9

Iron (II) precipitate is

Answer 9

Green

Question 10

Iron (III) is

Answer 10

Brown

Question 11

Carbonate + acid ——

Answer 11

Salt + Water + Carbon dioxide

Question 12

Silver chloride is

Answer 12

White

Question 13

Silver bromide is

Answer 13

White

Question 14

Silver iodide is

Answer 14

Pale yellow

Question 15

2 Steps for Halide testing

Answer 15

Add dilute nitric acid - removes carbonates
Add silver nitrate

Question 16

2 Steps to Sulfate testing

Answer 16

Add dilute HCl acid
Add barium chloride

Question 17

Barium sulfate is

Answer 17

White

Question 18

What can flame spectroscopy determine in a solution?

Answer 18

The metal ions present
The concentration of metal ions present

Question 19

Concentration of ion in Flame emission spectroscopy

Answer 19

Intensity of line

Question 20

Identification of ions in Flame emission spectroscopy

Answer 20

Distinct line

Question 21

What is potable water?

Answer 21

Water that has low levels of salts and microbes and it is safe to drink