5.3.2

Question 1

how can we identify transition elements

Answer 1

adding NaOH and record the colour of the precipitate formed

Question 2

what colour is cu2+

Answer 2

blue precipitate

Question 3

what colour is fe2+

Answer 3

green precipitate

Question 4

what colour is Mn2+

Answer 4

pink precipitate

Question 5

what colour is fe3+

Answer 5

orange precipitate

Question 6

what colour is cr3+

Answer 6

dirty green precipitate

Question 7

how to test for carbonates

Answer 7

-add dilute nitric acid
-efferevescence if carbonates are present
co32-(aq)+2H+(Aq)——–>CO2(g)+H2O(l)

Question 8

how to test for sulphate

Answer 8

-add dilute nitric acid
-followed by barium chloride
-if you get a white precipitate it will be barium sulphate
Ba2+(Aq)+SO42-(Aq)———->BaSO4(s)

Question 9

how to test for halides

Answer 9

-add dilute nitric acid
-followed by silver nitrate
cl-white precipitate
br-cream precipitate
i-yellow precipitate
Ag+(Aq) +x-(Aq)———->AgX(s)

Question 10

how to test for ammonia

Answer 10

-add some NaOH
-warm the mixture
-hold damp red litmus paper above and if it turns blue it means NH3(g) was present in the mixture