tests

Question 1

flame test?

Answer 1

nichrome wire dipped in HCl then the solid crushed into a powder.

Question 2

flame test colours?

Answer 2

lithium= red
sodium=  yellow
potassium= lilac
calcium= brick red
barium= apple green
copper= green

Question 3

iron (II) and hydroxide ions test for metal ions

Answer 3

green gelatinous precipitate

Question 4

iron (III) and hydroxide ions?

Answer 4

orange gelatinous precipitate

Question 5

copper (II) and hydroxide ions?

Answer 5

pale blue gelatinous precipitate

Question 6

lead (II) and iodide ions?

Answer 6

bright yellow precipitate

Question 7

ammonium ions and hydroxide ions?

Answer 7

ammonia gas given off and smells. makes damp red litmus paper go blue

Question 8

silver nitrate and chlorine?

Answer 8

white precipitate

Question 9

silver nitrate and bromine?

Answer 9

cream precipitate

Question 10

silver nitrate and iodine?

Answer 10

pale yellow precipitate

Question 11

silver and hydroxide ions?

Answer 11

brown gelatinous precipitate

Question 12

calcium and hydroxide ions?

Answer 12

white gelatinous precipitate

Question 13

zinc (II) and hydroxide ions?

Answer 13

white then slowly colourless

Question 14

aluminium (III) and hydroxide ions?

Answer 14

white then colourless

Question 15

HCl and carbonates?

Answer 15

will fizz to give off carbon dioxide.

Question 16

carbon dioxide test?

Answer 16

will turn limewater cloudy

Question 17

to identify a sulphate ion what do you do?

Answer 17

add HCl and barium chloride. white precipitate means a sulphate was originally made because the precipitate is barium sulphate.

Question 18

a test for hydroxide ions?

Answer 18

damp red litmus paper turns blue indicating an alkali

Question 19

how do you test for a nitrate?

Answer 19

warm with NaOH and aluminium foil. Al reduces nitrate ions to NH4+ ions. ammonium then reactis with NaOH to make NH3 and water. if ammonia is given off, then it smells and makes damp red litmus paper blue

Question 20

nitrate (V) react with Al to make an alkali giving off what?

Answer 20

• add NaOH, aluminium foil, or devardas alloy
• Al reduces nitrate ions to produce ammonia gas
• smells and damp red litmus goes blue

Question 21

how can you visualise TLC stuff

Answer 21

iodine

florescence

Question 22

what is an indicator for a.a?

Answer 22

ninhydrin

Question 23

how can you tell that you have oxidised a primary alcohol?

Answer 23

the dichromate ions goes from orange to green to leave you with Cr(3+)

Question 24

test for an alkene?

Answer 24

add bromine water or bromine, will go from orange to colourless

Question 25

what is the Fehlings test?

Answer 25

1. fehlings and sample
2. water bath
3. aldehyde = brick red precipitate
   ketone = nothing happens
   the red precipitate is copper (I) from the reduction of copper (II). the extra electron comes from the oxidation of the aldehyde to a carboxylate ion

Question 26

what is the tollens test?

Answer 26

1. silver nitrate and NaOH make a brown precipitate
2. add dilute ammonia solution until brown completely goes
3. water bath
4. add sample
5. aldehyde = silver mirror
6. ketone = nada
   diamminesilver ions reduced with electron comes from oxidation aldehyde to carboxylate ion. produces ammonia and silver