Test for positive ions (and ammonium ions- SC25

Question 1

what are tests for positive ions?

Answer 1

precipitation reactions involving sodium hydroxide

Question 2

how are ions tested for positive ions?

Answer 2

few drops of NaOH are added to test solutions

Question 3

what precipritate colour does iron (II) produce?

Answer 3

green

Question 4

what precipritate colour does iron (III) produce?

Answer 4

brown

Question 5

what precipritate colour does copper produce?

Answer 5

blue

Question 6

what precipritate colour does calcium produce?

Answer 6

white

Question 7

what precipritate colour does aliminium produce?

Answer 7

white

Question 8

what 2 metal ions produce white precipitate

Answer 8

aliminium and calcium

Question 9

How can one distinguish between aliminum and calcium in a test for positive ions? what results will you recieve?

Answer 9

adding excess NaOH - aliminum hydroxide forms a colouress solution while calcium hydroxide does not

Question 10

What is used in a test for ammonium ions and what is produced if positive?

Answer 10

dilute NaOH detects NH4+ ions and ammonia gas (NH3) is produced

Question 11

what smell does ammonia gas produce?

Answer 11

sharp smell

Question 12

how can litmus paper detect ammonia gas?

Answer 12

damp red litmus paper turns blue