Anion & Water tests

Question 1

Carbonate, CO32−

Answer 1

Add dilute acid, then test for carbon
dioxide gas
Result- Effervescence, carbon dioxide
produced

Question 2

Chloride, Cl− [in solution]

Answer 2

Acidify with dilute nitric acid, then
add aqueous silver nitrate
Result- White ppt

Question 3

Bromide, Br- [in solution]

Answer 3

Acidify with dilute nitric acid, then
add aqueous silver nitrate
Result- Cream ppt

Question 4

Iodide, I− [in solution]

Answer 4

Acidify with dilute nitric acid, then
add aqueous silver nitrate
Result- Yellow ppt

Question 5

Nitrate, NO3− [in solution]

Answer 5

Add aqueous sodium hydroxide,
then aluminum foil; warm carefully
Result- Ammonia produces

Question 6

Sulfate, SO42− [in solution]

Answer 6

Acidify with dilute nitric acid, then
add aqueous barium nitrate
Result- White ppt

Question 7

Sulfite, SO32−

Answer 7

Add a small volume of acidified
aqueous potassium manganate(VII)
Result- color change from purple to colorless

Question 8

Water test with chlorine

Answer 8

Turns blue to pink with the addition of water. (done using cobalt chloride paper)

Question 9

Water test with sulfur

Answer 9

Anhydrous copper (II) sulfate turns white to blue on the addition of water

Question 10

State the equation for water test w/ chlorine

Answer 10

CoCl2(s) + 6H2O(l) → CoCl2.6H2O(s)

Question 11

State the equation for water test w/ sulfur

Answer 11

CuSO4(s) + 5H2O(l) → CuSO4.5H2O(s)