Purpose:

To find the the pH and concentration of our everyday acid. We chose warheads, which has malonic acid.

 

Materials:

250ml erlenmeyer flask, 100 ml beaker, graduated cylinder, burette, warheads candy, scale, funnel, filter, phenolphthalein, 0.1 M NaOH (50mL), water (100 mL)

Procedure:

Grind up warheads candy into powder using mortar and pestle.

Mix 10g of warheads powder with 100mL of water.

Filter 10mL of water/warhead mixture into a flask (repeat two more times).

Titrate each time 10 mL is filtered with NaOH.

Data:

try 1: 0-7.1 (7.1 difference)

try 2: 7.1-13.9 (6.8 difference)

try 3: 13.9-21.1 (7.2 difference)

10ml of mixture

10g of powder, 0.5g acid- 0.5ml acid

average of 7ml used NaOH

 

Calculations:

0.1 M x 0.007 L = 0.0007 moles NaOH M1V1=M2V2

0.0007 moles acid

-log(0.0007)= pH 3.15

[H3O]= 0.0007

 

Conclusion:

The pH of malonic acid is 3.15. The [H3O] is [0.0007].