All test tube reactions

Question 1

What is the test for SO4 2- ions and result?

Answer 1

1. Acidify with HCL
2. Add BaCl

Positive: White precipitate of BaSO4

Question 2

What is the test for CO3 2- ions and result?

Answer 2

Add HCl

Positive: Effervescence CO2

Question 3

What is the test for OH- ions and result?

Answer 3

Damp red litmus paper

Positive: Red to Blue

Question 4

What is the test for halide ions and each of their results?

Answer 4

1. Acidify with HNO3
2. Add AgNO3
3. Add NH3 then conc NH3

Cl- White precipitate Soluble in NH3

Br- Cream precipitate Soluble in Conc NH3

I- Yellow precipitate Insoluble in conc NH3

Question 5

What is the test for Group 2 ions and results?

Answer 5

Add NaOH

Solubility increases down group

Add H2SO4

Solubility decreases down group

Question 6

What is the test for NH4+ and results?

Answer 6

1. Add NaOH
2. Heat
3. Damp red litmus

Litmus Red to Blue

Question 7

What is the test for Alkenes and results?

Answer 7

Add bromine water

Orange to colourless

Question 8

What is the test for haloalkanes and result?

Answer 8

1. Add NaOH and warm to remove halide
2. HNO3
3. AgNO3

Cl- White precipitate
Br- Cream precipitate
I- Yellow precipitate

Question 9

What is the test to distinguish between 1* and 2* alcohols and 3*?

Answer 9

1* and 2*
Add K2Cr2O7
Orange to green colour change

3*
No colour change

Question 10

What is the test for aldehydes and ketones and results?

Answer 10

Add Tollen’s solutions

Aldehyde: Silver Mirror
Ketone: No Silver mirror

OR

Fehlings solution

Aldehyde: Red precipitate
Ketone: No colour change

Question 11

What is the test for carboxylic acids and results?

Answer 11

Add any carbonate e.g. Na2CO3

Bubbles of CO2 gas produced