8-purity, Formulations, Chromatography

Question 1

Lithium flame test

Answer 1

Crimson (red) flame

Question 2

Sodiium flame test

Answer 2

Yellow flame

Question 3

Potassium ion flame test

Answer 3

Lilac flame

Question 4

Copper ions (+2) flame test

Answer 4

Green flame

Question 5

Copper (+2) sodium hydroxide added

Answer 5

Blue precipitate- copper hydroxide formed

Question 6

Calcium ions

Answer 6

Flame test-orange-red flame

Sodium hydroxide- white precipitate which does not dissolve when more sodium hydroxide added

Question 7

Magnesium ions +sodium hydroxide

Answer 7

White precipitate which does not dissolve when more sodium hydroxide is added

Question 8

Aluminium ions and sodium hydroxide

Answer 8

White precipitate which dissolves when more sodium hydroxide is addedd

Question 9

Iron(II) ions and sodium hydroxide

Answer 9

Green precipitate - iron hydroxide

Question 10

Iron (III) and sodium hydroxide

Answer 10

Brown precipitate-iron hydroxide

Question 11

How to test for carbonate ions CO3 2-

Answer 11

Dilute acid- bubbles of gas, that would turn limewater cloudy
Barium chloride with hydrochloric acid/silver nitrate with nitric acid- bubbles of gas when acid added

Question 12

How to test for sulfate ions SO4 2-

Answer 12

Forms white precipitate when barium chloride with hcl added (barium sulfate formed)

Question 13

How to test for chloride ions

Answer 13

White precipitate formed when silver nitrate with nitric acid is added (silver chloride)

Question 14

How to test for bromide ions

Answer 14

Cream precipitate formed when silver nitrate with nitric acid is added (silver bromide)

Question 15

How to test for Iodide ions

Answer 15

Yellow precipitate formed when silver nitrate with nitric acid is added (silver iodide)

Question 16

Crimson (red) flame

Answer 16

Lithium ion flame test

Question 17

Yellow flame

Answer 17

Sodium ions flame test

Question 18

Lilac flame

Answer 18

Potassium ions flame test

Question 19

Green flame

Answer 19

Copper 2+ ions flame test

Question 20

Orange-red flame

Answer 20

Calcium 2+ ions

Question 21

White precipitate which does not dissolve when more sodium hydroxide is added

Answer 21

Calcium ions (but can check with orange-red flame) or magnesium ions

Question 22

White precipitate which does dissolve when more sodium hydroxide added

Answer 22

Aluminium ions

Question 23

Green precipitate

Answer 23

Iron (II) ions when sodium hydroxide added

Question 24

Brown precipitate

Answer 24

Iron(III) ions with sodium hydroxide

Question 25

Dilute acid added and bubbles of gas which turn limewater cloudy are produced

Answer 25

Carbonate (CO3 2-) ions

Question 26

Barium chloride with hcl form white precipitate formed

Answer 26

Sulfate so4 2- ions

Question 27

Silver nitrate with nitric acid -white precipitate formed

Answer 27

Chloride ions

Question 28

Silver nitrate with nitric acid-cream precipitate

Answer 28

Bromide ions

Question 29

Silver nitrate with nitric acid- yellow precipitate

Answer 29

Iodide ions

Question 30

Flame emission spectroscopy

Answer 30

- example of aninstrumental method used to analyse metal ions in solution - sample put it a flame - light given out - passed thorugh spectroscope - out put line specimin - analysed to -identify metal ions ina solution - measure their conc

Question 31

Chemical methods

Answer 31

Resulsts chemical reactions

Question 32

Eg/. Chemical methods

Answer 32

- flame tests | - adding reagants to give precipitates

Question 33

Pros of chemical methods

Answer 33

Often simple to do

Question 34

Cons of chemical methods

Answer 34

Uses up sample

Question 35

Pros of instrumental methods

Answer 35

- small sample used - cost - accurate - gives lots info - sensitive

Question 36

Cons of instrumental methods

Answer 36

-machines;instruments can be expensive

Question 37

Identification of hydrogen

Answer 37

Burning splint held at the open end of a test tube of the gas Hdrogen burns rapidly with a pop sound

Question 38

Identification of oxygen

Answer 38

-glowing split inserted into a test tube of the gas relights in the presence of oxygen

Question 39

Identification of co2

Answer 39

- aqueous solution of calcium hydroxide(lime water) | - when co2 is bubbled through it- turns cloudy/miilky

Question 40

Identification of chlorine

Answer 40

-damp litmus paper put in chlorine gas, litmus paper is bleached and turns white

Question 41

Solute

Answer 41

Soldi that dissolves into the solvent

Question 42

Solvent

Answer 42

The liqy=uid that solute dissolves into

Question 43

Solution

Answer 43

A solute and solvent mixed together

Question 44

Formulation

Answer 44

-a mixture which has a purpose 0mixture must be in fixed proportion -eg. Fuels, cleaning agent, paints

Question 45

Pure substance

Answer 45

- single element or compound - not a mixture - eg. Pure milk - melting and boiling point can distinguish pure substanceds from mixtures

Question 46

Precipitates

Answer 46

-insoluble product that forms when two solutions are mixed and react together

Question 47

Chromatography

Answer 47

- as solvent moves up paper it takes solute - dont use wateer as too polar - solute dissolves into solvent - solute moves in and out of mobile and stationary phase - distance moved by solute depends on solubility and attractive forces between solute and chromatography paper

Question 48

Rf value

Answer 48

- quantative approach | - d by solute/d by solvent

Question 49

Why does pure substances look like

Answer 49

Single spot in all solvents

Question 50

What are the uses of chromatography

Answer 50

- seperating mixtures | - help identify substances

Question 51

Why some spots may not be seen

Answer 51

- components are colourless in solution | - dyes/chemicals same rf value

Question 52

Flame tets

Answer 52

- used to identify osme metal ions (cations) - if sample containing a mixture of ions is used - some flame colours may be mixed

Question 53

Metal hydroxides

Answer 53

- used to identifysome metal ions | - when mixed with metal ions- insoluble hydroxide precipitate may be producedd

Question 54

Carbonates

Answer 54

- dilute acids + carbonate ——> co2 | - co2 tested with limewater

Question 55

Halides test

Answer 55

Halide ions + silver nitrate solution+ dilute nitric acid | -forms precipitate

Question 56

Sulfates test

Answer 56

Sulfate ions + barium chromium solution + HCL | -white precipitate