Analysis

Question 1

Cu2+

Answer 1

Test: Flame test
Observation: Green/blue flame

OR

Test: Add NaOH(aq)
Observation: Blue ppt

Question 2

Al3+

Answer 2

Test: Add NaOH(aq)
Observation: White ppt, soluble in excess

Question 3

Na+

Answer 3

Test: Flame test
Observation: Yellow / Orange flame

Question 4

Cl-

Answer 4

Test: Add HNO3 + AgNO3
Observation: white ppt

Question 5

I-

Answer 5

Test: add HNO3 + AgNO3
Observation: yellow ppt

Question 6

SO42-

Answer 6

Test: add HCl + BaCl2
Observation: white ppt

Question 7

Br-

Answer 7

Test: add HNO3 + AgNO3
Observation: Cream ppt

Question 8

K+

Answer 8

Test: Flame test
Observation: Lilac flame

Question 9

Ca2+

Answer 9

Test: Flame test
Observation: Brick red flame

OR

Test: Add NaOH(aq)
Observation: White ppt, insoluble in excess

Question 10

Fe3+

Answer 10

Test: Add NaOH(aq)
Observation: Red-brown ppt

Question 11

Co32-

Answer 11

Test: add dilute acid
Observation: effervescence (co2 turns limewater cloudy)

Question 12

NH4+

Answer 12

Test: Warm with NaOH(aq), test fumes of NH3 with damp pink litmus
Observation: Pink litmus turns blue

Question 13

H+ or OH-

Answer 13

H+ : effervescence with a carbonate OR universal indicator / litmus turns red
OH- : universal indicator / litmus turns blue