C8: TESTING FOR IONS

Question 1

What is the test for +ve ions?

Answer 1

add NaOH

Question 2

What the result for Aluminium ions (Al^3+) when NaOH is added?

Answer 2

white precipitate formed (if NaOH is added in excess, precipitate re-dissolves)

Question 3

What the result for calcium ions (Ca^2+) and magnesium ions (mg^2+) when NaOH is added?

Answer 3

white precipitate forms

Question 4

What the result for copper II ions (Cu^2+) when NaOH is added?

Answer 4

blue precipitate forms

Question 5

What the result for iron II ions (Fe^2+) when NaOH is added?

Answer 5

green precipitate forms

Question 6

What the result for iron III ions (Fe^3+) when NaOH is added?

Answer 6

brown precipitate forms

Question 7

What is the test and result for carbonate ions (CO3^2-)?

Answer 7

-add HCl
-effervescence
(-test gas produced with limewater)

Question 8

What is the test and result for sulfate ions (SO4^2-)?

Answer 8

-add HCl and barium chloride
-white precipitate forms

Question 9

What is the test and result for halide ions (Cl^-,Br^-,I^-)

Answer 9

-add nitric acid and silver nitrate
-iodide ions form yellow precipitate
-bromide ions form cream precipitate
-chloride ions form white precipitate