9.1-9.9 Qualitative analysis

Question 1

Why must the test for ions be unique?

Answer 1

.You would never be able to tell which ion it was if more than one ion gave the same result

Question 2

What colour will the flame go if a Lithium ion is present?

Answer 2

Red

Question 3

What colour will the flame go if a sodium ion is present?

Answer 3

Yellow

Question 4

What colour will the flame go if a potassium ion is present?

Answer 4

Lilac

Question 5

What colour will the flame go if a calcium ion is present?

Answer 5

Orange-red

Question 6

What colour will the flame go if a copper ion is present?

Answer 6

Blue-Green

Question 7

If an aluminium Ion was present what colour precipitate would form?

Answer 7

White precipitate

Question 8

If a calcium ion was present what colour would the precipitate be?

Answer 8

White precipitate

Question 9

How can you tell the difference between Aluminium and Calcium ions if both form a white precipitate?

Answer 9

Add sodium hydroxide as Aluminium ions dissolve when excess NaOH is added

Question 10

If a copper ion is present what precipitate will it form?

Answer 10

Blue precipitate

Question 11

If Iron(II) was present what precipitate will form?

Answer 11

Green

Question 12

If Iron(III) is present what precipitate will form?

Answer 12

Brown precipitate

Question 13

How could you tell if an Ammonium ion was in a solid or solution?

Answer 13

.Pungent-smelling gas is produced

.Gas produced turns damp red litmus paper blue

Question 14

Describe the chemical test for Ammonia

Answer 14

.Makes damp red litmus paper turn blue
.It also forms a white smoke of ammonium chloride when hydrogen chloride gas from concentrated hydrochloric acid is held near it

Question 15

Describe the test to find if there is a Carbonate ion in a solid or solution

Answer 15

.Use dilute acid and identify the CO2

.If the gas produced bubbles through limewater and it it goes cloudy it is CO2

Question 16

Describe the test to find if there is a sulfate ion in a solid or solution

Answer 16

.Add dilute HCL followed by barium chloride solution

.A white precipitate will form when sulfate ions are in this solution

Question 17

Describe the test to find if there are chloride, bromide or iodide ions in a solid or solution

Answer 17

.First, add dilute nitric acid followed by silver nitrate solution
Chloride gives a white precipitate
Bromide gives a cream precipitate
Iodine gives a yellow precipitate

Question 18

What can be detected using instrumental methods?

Answer 18

Elements and compounds

Question 19

Give an example of a instrumental method

Answer 19

.Gas chromatography

.Mass spectrometry

Question 20

What is a flame photometer an example of?

Answer 20

An instrumental method used to analyse metal ions n a solution

Question 21

How do you work a flame photometer?

Answer 21

.Sample is put into a flame and the light given out is passed through a photometer

Question 22

What is the output of a flame photometer?

Answer 22

.Output is a line spectrum that can be analysed to identify the metal ions in the solution and to measure their concentration