Test For Ions

Question 1

H+ ions

Answer 1

Litmus
Blue -> red

Question 2

OH-

Answer 2

Litmus
Red -> blue

Question 3

CO3 2-
Carbonate test

Answer 3

Acid -> effervescence
(Salt + h2o + co2)

Question 4

SO4 2-
sulphate ion

Answer 4

1) acid to remove co3 2- as BaCO3 is insoluble
2) BaCl2 -> white precipitate of BaSO4

Question 5

Halide tests

Answer 5

1) acid removes carbonates - BaCO3 is insoluble
2) BaCl2 removes sulphate - AgSO4 is insoluble
3)AgNO3
-white precipitate = Cl-
-cream precipitate = Br-
-yellow precipitate = I-

Question 6

Identify halide (specific)

Answer 6

1) dilute NH3 -> precipitate dissolves = AgCl
2) concentrated NH3 -> AgBr dissolves
3) AgI - no change

Question 7

Precipitate

Answer 7

Insoluble solid form from two soluble compounds reacting

Question 8

How to test if all of a compound has reacted

Answer 8

Test for the eye on the compound positive result indicates not all of the compound has reacted as it would then be s or g (not reactive with aqueous solution )

Question 9

Test for NH4+

Answer 9

KOH warmed
Gas turns DAMP red litmus blue

Question 10

how to separate 2 liquid layers

Answer 10

use a separating funnel

Question 11

test for ammonium ions

Answer 11

adding (K)OH solution and warm gently.
positive result - ammonia gas turns damp red litmus paper to blue