Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

A Level Chemistry > Tests for anions, cations, functional groups... > Flashcards

Tests for anions, cations, functional groups... Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

Test for acid/base character

A

acid- red

base- blue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Flame test for Li+

A

Red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Flame test Na+

A

orange/yellow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Flame test K+

A

lilac

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Flame test Rb+

A

red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Flame test Cs+

A

blue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Flame test Mg2+

A

no color

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Flame test Ca2+

A

brick-red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Flame test Sr2+

A

crimson red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Flame test Ba2+

A

green

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Test for CO32- and HCO3-

A

add acid(aq)
bubbles of co2 observed
use delivery tube to pass gas through limewater
limewater turns cloudy, CaCO3 formed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Test for NH4+ ions

A

add NaOH(aq) and warm gently
pungent smell given off
turns damp red litmus paper blue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Test for SO42-

A

Add BaCl2

white ppt of BaSO4 formed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Test for Halides

A

HNO3 followed by AgNO3
Cl-:white ppt soluble in ammonia
Br-: cream ppt soluble in excess ammonia
I-: yellow ppt insoluble in ammonia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Test for Mg2+

A

Add NaOH: white suspension

Add more NaOH: insoluble

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Test for Ca2+

A

Add NaOH: white suspension

Add more NaOH: partially in soluble

17
Q

Test for Sr2+ and Ba2+

A

Add NaOH: soluble

Add more NaOH: soluble

18
Q

Test for Zn2+

A

Add NaOH: white ppt soluble in NH3
Add more NaOH:ppt dissolves
Zn is amphoteric

19
Q

Test for Al3+

A

Add NaOH: white ppt
Add more NaOH: ppt dissolves
Al is amphoteric

20
Q

Test for Ag+

A

Add NaOH: dark brown ppt soluble in NH3

Add more NaOH: insoluble

21
Q

Test for Cu2+

A

Add NaOH: blue ppt soluble in excess ammonia blue solution

Add more NaOH: insoluble

22
Q

Test for Fe2+

A

Add NaOH: white/green ppt slowly turns brown when exposed to air
Add more NaOH: insoluble

23
Q

Test for Fe3+

A

Add NaOH: brown ppt

Add more NaOH: insoluble

24
Q

Test for Cr3+

A

Add NaOH: blue-green ppt soluble in NH3 to give violet solution
Add more NaOH:ppt dissolves to give green solution

25
Q

Test for Co2+

A

Add NaOH: blueish ppt slowly turns pink, dissolves in NH3 light brown solution
Add more NaOH:insoluble

26
Q

Test for Ni2+

A

Add NaOH: green ppt soluble in NH3 to give blue solution

Add more NaOH: ppt doesn’t dissolve

27
Q

Test for Mn2+

A

Add NaOH: off-white ppt turns brown in exposure to air

Add more NaOH:insoluble

28
Q

Test for halides with conc H2SO4

A

Cl-: steamy fumes of HCl
Br-: steamy fumes, brown vapour
I-: steamy fumes, purple vapour, black solid

29
Q

Test for bromides

A

add chlorine water
orange solution
Effervescence may be produced

30
Q

Test for alkenes

A

add some bromine water

color change from orange to colourless

31
Q

Test for -OH groups (not phenols)

A 
add PCl5
misty fumes of HCl
or
add a small piece of sodium
effervescence
32
Q

Test for carboxylic acids

A

litmus paper turns red-ish.
Add a carbonate/HCO3​ −​
Effervescence (CO2​ )​

33
Q

Test for aldehydes and ketones

A

Add 2,4-DNP (Brady’s reagent).

An orange precipitate is formed upon reaction with C=O group of aldehyde or ketone.

34
Q

Test to distinguish aldehydes from ketones

A

Add Tollen’s Solution(ammoniacal AgNO3​)​.
Aldehydes give a positive test and a silver mirror is observed.
Ketones cannot be oxidised, so no change observed)
or
Fehling’s test.
Aldehydes give a positive test and form a brick red precipitate.
Ketones don’t react so the solution stays deep blue).

35
Q

Test for methylketones, ethanal, ethanol, and methyl secondary alcohols

A

Iodoform Reaction
Warm with iodine and sodium hydroxide.
Yellow precipitate.
Antiseptic smell (triiodomethane, iodoform).

36
Q

Test for primary/secondary alcohol and aldehydes

A

warm with acididfied K2Cr2O7

color change from orange to green

37
Q

Esterification test

A

Gently warm an alcohol and carboxylic acid in presence of conc. H2​ S​ O4​
Should produce a compound with a characteristic smell

38
Q

Solubility Test

A

Compounds with groups that can form H-bonds may be soluble in water, (e.g. amines, alcohols, carboxylic acids etc.)
Some carboxylic acids may not be soluble in water, but may be soluble in alkaline solution (due to formation of RCOO−​ )​ .
Same goes with amines. Some may not be soluble in water, but will be soluble in acidic solution (e.g. formation of RNH3​ +​ )​

A Level Chemistry (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions